Sunday, April 9, 2017

The charge controller box

On the lower wiring schematic, there is a box that needs a bit more explanation.  During charging, the charge controller monitors the battery string.  If the batteries can accept more charge, the charge controller provides a small signal to allow a charger to operate.  This small signal is then sent to a solid-state relay that then allows 110V power to the charger,

Solid state relays are pretty neat.  They operate just like traditional electromagnet relays but have no moving parts to fail.  Just provide a small DC voltage in to the low voltage terminals and 110V will then be allowed to pass through the other terminals.  At the time I purchased my relay, I wasn't sure how much heat they would generate.  So, I purchased the optional aluminum heat sink.  To be extra careful, I also figured a small PC fan could be used to carry the heat away.  However, I was faced with a problem.  Where do I fit all this stuff?

Since there wasn't much room within the BugE, I used an external solution.  I happened to have an old PC power supply box.  After removing the insides, I found it provided just enough room for the relay, heat sink, cooling fan and a 110v outlet to plug the charger into.  The resulting box is shown below. When I want to charge the BugE, the 48v charger plugs into the top of the box.  The box then plugs into the side XLR port to get it's logic signal.  The box then gets plugged into the wall (short cord shown for the photo, a larger patch cord to reach the wall is used instead).  The black box on top is a plug-in 12v transformer to  power the fan.  The fan cools the heat sink and it's sound also indicates the box is passing 110v.   It's not too elegant looking, but it works.

Wednesday, March 4, 2015

Awaiting the summer...

Snow Snow Snow! Can't wait to bring the BugE out again.  For now, it sits in the garage on blocks occasionally drawing on the power cord to top off it's batteries.   For those who need a green memory while awaiting motorcycle season, here's a photo a friend of mine forwarded to me from last summer.
As for upgrades, not much has changed. I bought replacement tires from and had them put on at my local motorcycle shop.  So far, they are holding up well.  I also added some LED lights for the cargo space. 

At some point, I intended to post a 12v wiring diagram.   However, my box of "round-tuits" is rather empty.  In it's place, I have a large collection of "Honey do's". Those who are married know what I'm talking about. That is, "Honey, do this, Honey do that...."    Fortunately, for those who would await my sage wisdom the 12V wiring isn't that sophisticated.  The upper wiring is almost identical to a regular motorcycle.  That is, the design is driven mostly by the speedometer connections.  Fortunately, many speedometer kits come with 12v wiring examples.  The 12V wiring example I used is very close to what would be used on a normal street bike with the exception being that the fuel gauge in the speedometer currently reads empty.  I haven't found a really good way of representing estimated range as an E-F reading.  There are just too many variables when it comes to electric vehicle range.

Should anyone want it, I have made my lower wiring harness available as a downloadable PDF from my Google drive.  It can be found HERE

Tuesday, September 16, 2014

Lower wiring harness for lithium BugE.

The lower wiring harness diagram is available as a downloadable PDF that can be seen by clicking HERE .  The text below explains how this design came into being. So far, the circuit has been working well. I have color coded the wiring to make the circuit easier to follow.  Upper wiring block is negative (both 12V and 48V).  Lower wiring block is positive. Red is 12V, Yellow is 48V and so on. Also, although both grounds use the same wiring block, they remain isolated from each other.  After burning out some expensive components trying to match these grounds, I finally learned that attaching the 12V ground to the traction battery ground  is just an overall bad idea!  With that being said, let's discuss the circuit as it is now.

The whole circuit appears to be quite complicated due to the special needs of the lithium pack and it's battery management system. So, I've divided up the circuit for easier understanding. 

This is the basic lithium drive circuit, extracted from the main diagram.  Although the cells are lithium, the drive circuit isn't that much different from the instructions that come with the BugE for a lead-acid pack.   When the red key is turned on, it engages the safety contactor that allows pack voltage to reach the speed controller (we need a safety contactor and heavy fuse so a short doesn't blow up the pack). However, before power can pass through the speed controller, there is a second requirement to be met.  Federal motor vehicle standards require a headlight interlock to prevent the vehicle from being powered if a headlight isn't on.  To do this, the 12V headlight circuit (not shown) engages a relay.  The relay then completes the circuit that allows voltage to at last reach the "key" input on the speed controller.  Once the "key" input is turned on, the speed controller then can pass pack voltage proportional to throttle position.  After the speed controller is the reversing switch.  Depending on it's position, the reversing switch then passes power to the DC motor (and powers it's magnetic field) to create forward motion or reverse motion.

When  it comes to charging the BugE, lithium batteries can be quite problematic.  If a lithium battery discharges too low, it can be ruined. If the cells are charged too much, there is a possibility of fire.  So, a battery management system (powered by 12v) has been installed.  Below shows the battery pack with the BMS installed.  

  To prevent cells from being ruined by undercharge, electronic modules are put on each cell to monitor voltage. They participate in a loop which is monitored by a circuit board powered by a 12V battery. If any of the cells get below a threshold voltage, the loop is broken and the circuit board sounds an alarm with an on-board buzzer.   When charging, each cell must not go over a threshold voltage. So, in charging mode, if any one module detects an over voltage, it breaks the loop.  When that happens, the control circuit cuts power to a solid state relay that is used to allow 110v to reach the battery charger.  Without power from the BMS, the solid state relay passes no power to the battery charger.  Unfortunately, the BMS control circuit isn't too smart.  It must be put in either "driving mode" or "charging mode" which is accomplished by a key switch. Unfortunately, if left in driving mode, while charging, there will be no over voltage protection.  This can  possibly cause a fire.  So, a BMS indicator lamp has been added to remind the driver that the BugE BMS must be taken out of driving mode before batteries can be charged.   Also, BMS systems take energy to run.  So, a toggle switch has been installed to turn off the BMS when it's nether charging or monitoring the pack while driving.

Although the 12V lights could be powered by a DC-DC converter they are not.  Instead, all 12V loads are powered from the same 12V motorcycle battery that powers the BMS.  This means if the main pack becomes depleted, the 12V system can still power lighting (which includes hazard lights).  The 12V circuitry in the cowl has been separated from the lower wiring circuit such that you can "unplug" the cowl, lift the upper body off the vehicle, then test it's 12v circuit elsewhere simply by connecting a positive and negative to any random 12v battery.  Due to this circuit independence, I have represented the cowl lights, speedometer and horn simply as a box called "Cowl lights".

Currently, the BugE, uses two external chargers.  One for the 12V battery and the other for the main pack. To eliminate the need for two chargers, I will soon be installing a 12V DC-DC converter (and charge controller) to charge the 12V battery from the main pack while the vehicle is in driving mode.

Wednesday, August 20, 2014

Maintaining the BugE - Motor testing

The BugE is a kit so builders have installed a variety of motors in them. The BugE motor that is closest to "stock" would be the Advanced DC motor 140-01-4008 that was sold by EV Parts in their BugE electric package. The motor has two very nice features. First, it needs no modification to bolt into the mounting plate on the BugE swing-arm.  Second, it can be run in reverse.  That feature makes the BugE easy to park, unlike a typical motorcycle that usually has no powered means of reversing out of a parking space.

However, there may come a day when there is a problem in the traction circuit may require some troubleshooting.  Fortunately, the motor is an item that is relatively easy to test.  The Advanced motor, unlike a typical toy motor, has no permanent magnets. Instead, electromagnets are used.  To see how the motor works, a test table can be made by strapping down the motor to a table. A car battery can provide enough current but keep the speed low enough to avoid "over spinning" the motor. To test, make a small jumper for the field coils then apply power to the commutator terminals. When 12v is applied, it will rotate with lots of torque and relatively fast, but not fast enough to destroy itself.   It really only needs one strap since the rotation force from start up without a load isn't too much but it's better to be safe than sorry!

Why 4 terminals?  It's a rather flexible arrangement when it comes to using the reversing switch as sold by EV parts.  For those who like schematics, here's a drawing.
Clockwise direction
Connect A1 to one battery terminal
Connect A2 to S2
Connect S1 to other battery terminal
Counter Clockwise
Connect A1 to one battery terminal
Connect A2 to S1
Connect S2 to other battery terminal

Sunday, December 22, 2013

Using the "Tiny" BMS system

The old system using lead-acid batteries lacked range but it was very simple to maintain.  Just plug in the string of batteries.  Rely on self-powered balancing modules to keep the batteries even.  For 12V needs, use a DC-DC converter to convert 48V to 12V.  It was simple.  It was reliable.  But it lacked range.

The new batteries have better performance but they are very fussy.  The new Battery Management System (BMS) requires a separate 12V battery.   That requirement made the new wiring system much more complicated.  In order to simplify wiring, I decided to use a common ground between all systems.  After all, ground should be ground right?  Anyway, the cowl lighting checked out OK using the 12V battery.  The BMS also worked just fine on the 12V accessory battery.  The 48V circuit also seemed to check out as well as I could test it. At last, it was time to make a big happy common ground between the main pack, the 12V accessory battery and the DC-DC converter.  The charger was off as well as the ignition but the main battery pack and accessory battery pack were of course live. So, it was time to put the 12V and 48V grounds together - POW!  Stupid me!  I hadn't checked first to see if there was any potential between the grounds!

In spite of a faint electric smell, the main systems seemed to check out.  The DC-DC converter, all 12V lighting, including my digital speedometer seemed to be unharmed. The speed controller (and traction motor) also seemed to work fine.  However, there was one very expensive exception.  My Elite power BMS now had no display!  Not only that but the secondary display didn't work either!  I apparently fried the LIN HUB or the main BMS module.  Either way, it was a major problem since both components were no longer sold by Elite Power.  What was worse was that new BMS components from Elite power are rather expensive!

Unfortunately, the problem was worse than I realized.  The idea of tying together the traction pack ground and ground to the accessory battery was flawed from the start.  If I have even the tiniest voltage leak, I'll build up potential again, have the sparky problem again and probably blow out yet another component on the 12v side. So, I've used what I've learned to redesign the 12V wiring to be completely isolated from the 48V circuit. 

As for replacing the BMS, the TinyBMS system looked relatively simple, scalable and was not too expensive.  In a nutshell, here's how the system works.  The modules balance each battery and also participate in a series control loop much like a home-alarm system circuit.  If anything strange happens to an individual cell such as it going too high in temperature or dropping too high or low in voltage, that module will break the loop to signal the main board that all is not well.  The the control board has an on-board buzzer that can sound an alarm and has an optional circuit to reduce the throttle to a lower power "limp home" mode. When charging the batteries, the modules can trigger a charger cutoff (if the charger supports that kind of signal).  The the status of each battery can be seen via LED blink patterns on each module.   

The modules were available for 3.6Volt or 3.8Volt calibration.  My battery formulation, being LiFeMnPO4 was different than the LiFePO4 this BMS was made for.  So, I wondered if I could use this BMS. The batteries that I have measured around 3.2 Volts.  However, I seemed to recall values as high as 3.6v displayed on the previous BMS system in the past when the batteries were charging.  Although the upper charge voltage may be in question, I believe on each type of battery I'm aware of, the discharge voltage should be no lower than 2.8v. So, I went with the 3.6Volt type.

There are other problems with this inexpensive system.  The first question I had was to see if my charger could be controlled with this board as it was with the previous board.  After some research, I found rather than expecting a simple logic signal level of say 3.3 or 5V, the charger I had requires a digital protocol called CAN to turn off the charger. Fortunately, the absence of any signal allows the charger to default to being on. So, as a workaround, I've ordered a solid state relay (and heat-sink) so the new BMS board can simply turn off current to the charger.

Unfortunately, the simplicity of the BMS board is also problematic.  The BMS board can detect if the series battery circuit has a problem - but not WHY it happened.  An open in the string could be caused by a battery being "empty" from discharge or "full" from charging.  The solution to this is to have a 12V input signal called "ignition" .  To accomplish this, a key-controlled circuit and pilot light show when the circuit board monitors does not protect the batteries from overcharge. 

In summary, what I gain from this BMS system is a low price and relative simplicity.  The BMS protects against catastrophic fire,  undercharge and provides shunt based cell balancing.  Each module also provides visual LED status on each cell to tell what each module is doing.  That's really nice since you can actually see cell balancing in action.  What I don't have is granular per-cell voltage information I can read from the dashboard nor any estimate of how much energy is probably left in the pack.

Sunday, November 3, 2013

BugE Re-wire

For the longest time, the BugE reminded me of some sort of futuristic hovercraft.  Ever since I got it, I've wanted to put some lighting on the BugE to give it a "riding on neon" effect.  However, I never got around to it.  The other day, I was looking at LED lighting and the idea came up again.  So, I've decided to add some "bling" to the BugE.  However, before I do that, I've decided to upgrade the wiring based on what I've learned from it's time in the field.

So, based on my experience, I'm going to make an effort to improve the wiring. The cowl wiring seems to be OK for now.  It's got a reasonably simple layout that is relatively easy to troubleshoot.  Other than possibly changing out the headlight for an LED headlight, I'm reasonably happy with it.  The lower wiring isn't so nice.  It became a rats nest ever since I decided to add lithium batteries (due to the extra battery management circuitry).  So, I've ripped out the lower wiring and I'm starting over.

Perhaps the most important feature if the new wiring is to use a true wiring block.  Unlike my past wiring which used numerous taps and in line fuses that was almost impossible to troubleshoot, this new wiring will come together to one location similar to a car.  Fortunately, the battery pack is small enough that a wiring platform can be installed next to it.

Here are the requirements for the new wiring

1) The traction battery (The big battery) needs to be electrically isolated from the rest of the system.  That means NO COMMON GROUND between the accessory loads and the traction battery.  The 12V system should run off of either a totally separate 12V battery or use a good ELECTRICALLY ISOLATED DC-DC converter. The converter should have (+ -) wires for the 48V side and (+ -) for the 12V side.  Although it is very tempting to connect those grounds together to make wiring simpler I burned out my older BMS system trying to make that work.  After that expensive lesson, I've learned -  keep those grounds isolated!

2) Overcharging a lithium battery can raise it's temperature. That not only can damage the cell but it can also cause a fire.  So, it's VITAL that no cell is overcharged.  That means the string of batteries needs a BMS system.  Most BMS modules work by monitoring the terminal voltages of each cell (and temperature too).  If any cell goes over voltage or over temperature, the battery module will try to shunt electricity away from the cell if it can.  If it can't it has a mechanism to tell the BMS to tell the charger to stop charging the whole string.

3) When installing a BMS system, it's really easy to damage the individual BMS modules.  Before installing a BMS system, disconnect an on-board charger before installing them.  Turns out the battery charger has some capacitance in that has the potential to fry individual modules.

4) Although on the surface, the wiring doesn't look all that different, the addition of a wiring block eases troubleshooting and also allows for quick wiring changes.

Sunday, September 11, 2011

Unusual problems found with "normal" use patterns.

Here's what I've found so far as the BugE is used for it's intended use - a pure electric commuter vehicle that operates in cool rainy conditions while keeping the occupant free of windchill and rain.

First, in terms of BugE specific issues, I've noticed more tire wear with the front two tires with little wear on the drive tire. This suggests my 'toe' is out of adjustment. I'm guessing too much toe-in. So, an adjustment of the steering rods will be needed. Fortunately, this is a simple task. Visit the express links on the right to see how this is done.

Another unusual incident happened. It has to do with the BMS system. This type of BMS is no longer sold and has been replaced with a more reliable system. Unfortunately, I have the older setup. So, I came home to find the meter showing my batteries were rather low . I knew this, only due to noticing the BMS indicator lights were completely off. What apparently happened was that the DC-DC converter was doing a steady draw down of the batteries to power the BMS. However, the BMS wasn't triggering the AC charger to replenish the main pack. Finally, the DC-DC converter had the sense to cut off. However, the lead-acid battery discharged completely (turning off the BMS and it's indicator lights.) I'm sure the lead-acid battery took some damage but it's duty is normally rather light. So, it may have survived well enough to remain in service.

Fortunately, the main pack was not completely drawn down, just low. The cause was apparently due to a faulty LIN HUB. It failed such that it would only work if I bent the connector. When bent, all components seemed to work. When not, nothing worked. Unfortunately, when I tried solving the connector problem by trying to solder on a more robust replacement connector, I managed to loose what little function that circuit board still had. Unfortunately, it's a multi-layered board so it's beyond my ability to repair.

So, I removed the board, did an unbalanced charge of the pack to 50V and eliminated all parasite loads. Although 50V was not a full charge, it hopefully kept the lithium batteries in a safe state. Meanwhile, my vendor shipped me a replacement hub. Once replaced, the BMS returned to normal operation. Hopefully, the batteries are OK. We'll see if this is true in the next range test.

The last failure was severe enough to get my BugE trucked home. At times, if I accelerated even slightly, the vehicle stopped. After powering the vehicle on/off several times, the problem would go away. When I first noticed this, I thought the fault might be in the spade connectors I used for the throttle cable. So, I soldered the throttle wires to the speed controller inputs. This helped for a while, then the failure returned more often. So, this caused me to think the throttle potentiometer was at fault since it seemed to have similar symptoms to my previous throttle failure.

But no, these electric cars can be sneaky. Testing out the various components with a multimeter showed what the real cause was. After putting the rear tire up on blocks, I measured various voltages along the system. I found the potentiometer in the throttle was working just fine. However, the contactor (also known as the solenoid) was giving a voltage difference across it's terminals when engaged. This was not good since it's supposed to simply act as a hunk of wire between it's terminals when active. In fact, that's how I tested my hypothesis that the solenoid was at fault. I put a hunk of wire across the terminals. Sure enough, the motor driven by the speed controller worked just fine. So, I've ordered a new solenoid, at nearly $100 bucks. Hopefully, after installing the new one, I can take apart the old one to salvage it for a spare. It did cause me to question why these solenoid's are needed at all. For an explanation, look HERE.

Sunday, September 4, 2011

September 30, 2011 - My first commute!

At last. It was time for my first real commute from Auburn NY to Wells College in Aurora NY. Russel Watson's "Faith of the Heart" song came to mind when I took off on this historic journey.

Although the BugE will do 50MPH on flat ground, this test wasn't a speed trial. Rather, it was to figure out the speeds that will be fast enough to be useful yet be slow enough to not loose too much energy to wind resistance.

Distance was just over 20 miles. Morning temperature was 60 degrees and sunny. Canopy practically eliminated windchill. Speed was kept at a minimum of 30mph, up the gentile slope to the ridge line. Along the top, maintained 35mph. The journey was so pleasant that I overshot my planned turn. Fortunately, I had an excess of charge so I could take the next turnoff which made the journey slightly longer than planned. The last 2 miles downhill were done at 45. Arrived with 40% of charge still left. Commute time was 45 minutes which was two minutes longer than I had planned.

The BugE recharged at the Stratton Science Building where it was put on exhibit for the day. Charging was done before noon. At the end of the day it was time for the return journey. Rolling the BugE out of the building, the outside temperature was 80 degrees & humid. This caused a temporary fog on the canopy that quickly dissipated in the sun. I did the long climb up to the ridge at 25mph to see if a lower speed would help conserve the battery. It did. Once half way up the hill, I maintained speeds of 30-35mph. Since I had more charge than expected, I took the last 2 miles home at 45mph. Pulling into my driveway, I still had 1/3 charge left.

The trip had one noteworthy incident.
The throttle didn't work! So, I exercised the interlock relay several times. Then, the throttle worked. When I returned home, I tried some contact cleaner compound on the throttle spade connectors. That seemed to fix the immediate symptom. However, this likely isn't the real cause. I suspect the interlock arrangement I have may be at fault. So, I'll be doing a wiring change to test this hypothisis.

Monday, August 29, 2011

BugE Q & A

This blog posting is a partial response to some questions fermi_of_borg had in his BugE build.

The first photo shows how I oriented my direction switch. I found it was easiest if I had the forward direction pointing backward. However, this is probably opposite of what people normally would think when it comes to direction. I had to remove quite a bit of material with a Dremil tool to get a sufficient sized notch for the switch to go into. I decided to go with a notch instead of a hole since I open and close the battery compartment quite often for small adjustments. Now, no need to remove the handle!

The second photo shows the switch orientation without the cover. The direction switch is held in place with a couple of "L" brackets attached to a platform I made from a cutting board I bought at Wal-Mart. It's cheap, easy to cut, non conductive and needs no painting. Anyway, In the lower left is a little photo of a wiring change I did. In the original 48V wire diagram two wires were to be attached to a contactor terminal. Problem is, it's quite a tight space. So, I decided to attach the two wires together instead at the top terminal of the reversing switch. Electrons don't care which end of a wire they are on. To them, one terminal of a wire is identical to the other terminal of the same wire.

When it comes to connecting the lug rings, the type of nuts should connect very TIGHT! Using Nylock nuts will help. Also, double check the little screws on the lithium battery pack. They should be tight too. One way I happened to find a couple of a loose screws that I had forgotten to fully tighten was when my BMS said it had a "volt diff" error when I accelerated. Inspecting the pack, then tightening the loose terminal screws got rid of that error.

Last is a photo of my BMS wiring harness which is an example of perfection being given up for progress. It's ugly, but it works. Making a better harness will be a winter project. Meanwhile, this mess seems to work for me right now.

Sunday, August 28, 2011

Another range test

This range test was a 22 mile test to simulate a commute in terms of distance and hill climbing. This would be to the half way point, then do a return on one charge. First part of journey was at going to half-way point on relatively flat ground, then downhill from 860ft to 420 ft. Speed as before was kept between 30-35mph. At bottom of hill, I briefly tested battery recovery. Unlike a lead-acid pack, parking for 5 minutes showed no significant battery voltage recovery from the batteries in the main pack. Then back up the long slope at 15-25mph. The remainder leg home was done at 40-45 over the flat and downhill sections of road.

However, as I feared, my charge controller could not charge the accessory battery fast enough to keep up with usage. So, near the last mile of the journey, the 12V battery became weak enough to make the headlight interlock relay de-energize. So, the main pack still had 25% charge left but I couldn't go! No problem. I pushed the BugE to the side of the road. Turned off all navigation lights. Then waited 5 minutes for the charge controller to catch up. Then quickly proceeded home. Still had 20% left.

What this says is either that I'll either need to increase the accessory battery size, reduce loads or use a faster method using the DC-DC converter to re-charge the accessory battery while under-way. Too bad I can't find a reasonably priced DOT approved LED headlight for a motorcycle! Hopefully, lower cost LED headlights will appear soon.

Sunday, August 14, 2011

Lithium charger mounting

When using a lead-acid pack, I found an external lead-acid charger arrangement worked for me. However, the new lithium battery charger is larger, more expensive and has a really wimpy data cable that would quickly be destroyed through repeated connects and disconnects. So, I've decided to find a way to mount the charger so it does not need to be removed for each journey. To the left, you can see the end result. The charger has sufficient ventilation to keep cool. It also allows inspection of it's indicator LEDs on the end of it.

To the right is an image of how the holder just before it was installed. To mount, it's bolted in with nylocks and washers to the fiberglass battery pan structure. If assembled correctly, the charger should just "snap" into place. The only cable modification I needed to do was to lengthen the battery charger data cable so it could reach the "LIN hub". I suspect a "new" BMS system would only provide connectors & cable without being assembled, providing an opportunity to make cable lengths correct the first time.

Parts & tools required:
6ft piece of angle iron (you'll have some left over)
an angle iron bender (or use a vise & hammer)
scratch awl
tape measure or ruler
(10) 6-32 flat head screws with matching Nylock nuts
(4) washers - used for mounting to the Plexiglas battery tray
spray paint and primer
zipties (to run data and power cable to battery tray)

Sunday, August 7, 2011

Range tests

One of the most frequent questions I get asked usually includes the phrases, "How far and at what speed?" Due to these factors being dependent on conditions of the day, It's an impossible question to accurately answer. However, I can say this.

I did my first extended range test today. My route to work is 20.3 miles. I decided to go to the halfway point on the route I plan to take to work. According to the GPS, I start out going to work at 620ft above sea level. Then took several small hills for an average climb height to 860ft. I figured if I had 75% of the pack left at that point, it's likely I could make it to work with a comfortable reserve since the remaining part of the journey is either flat or down hill. Once at work, the plan would be to charge up during the workday for the return trip.

For this test, temperature was around 80 degrees, overcast, with occasional sprinkles of rain. Travel through town was stop and go which limited speed to around 25mph. Once out of town, roadway turned to tar & stone. The roadway outside town had enough bumpy areas that I limited my speed to between 30 and 35mph. Visibility was very good. I was followed briefly by one car. Otherwise, I saw only three cars going in the other direction. For the return part of the journey, I decided to take a faster route home. Speed was kept to about 40mph for most of the journey. However, once I encountered the smooth road of the arterial highway, I decided to speed up to 50mph for about a mile. No problem. I returned home with 60% of charge left.

Tuesday, August 2, 2011

First test drive on the lithium pack

Woha! The new battery pack makes this BugE perform much better! I decided my performance test would be at night. I drove in a mix of conditions with stop-and-go traffic along with hills. Total mileage was just over 10miles. I tried to keep speeds at least 30mph and go 40mph where I could. Passing cars was fun and I could even do so going up hills! At the end of the test, I decided to do a speed test on flat straight road. For the speed test, I sustained a speed of 50mph over 2 miles! At the end of the journey, pack still showed 60% of capacity left.

I decided to keep the retro analog meter to see how acceleration affected the pack. I noticed that the pack was either in white (full) or upper green at all times even during acceleration. I was worried that the 12V accessory battery would be depleted but it apparently has enough capacity to keep the lights relatively bright. Although I didn't have a digital meter, I did observe that headlight brightness seemed to be unchanged through the journey. The lithium pack also seems to have other benefits too. For example, braking and acceleration seem to both be better. Also, the BugE seems to deal with bumps better too.

The drive was not problem free. The BMS electronics have problems. For example, the LED readout has two LEDs that have already failed. Fortunately, I have the larger readout I can use instead. Also, the wiring seems to be of all the wrong lengths. I'm guessing this is because in it's original installation, the LIN HUB and all instrumentation was probably installed in the dashboard rather than in the battery compartment.

Still to do. The BMS system works but shows an error when the battery charger isn't present. So, next step is to mount the battery charger in the cargo area.

Sunday, July 31, 2011

Charging up....

At last, the batteries are installed and the wiring is connected! The pack is doing it's first charge cycle. Along the way, there were some interesting incidents.

Upon connecting the LIN HUB for the first time, the LED indicator panel showed a red LED "wiring fault" and the main display showed that the "battery capacity" was 0%. Yet no alarms were showing and going through the screens, it appeared as though each battery circuit board was being polled successfully. Also, when the charger was plugged in, the individual battery voltages seemed to be charging correctly. The fix was simple. Leave the charger plugged in. Then go through the settings. I found the unit was set as a zero AH pack. So, entering 60AH for my 16 cell pack size turned off the fault LED and updated the bar graph to show 100% capacity. The main pack, fully charged, shows 53.8V.

Another interesting incident. When I powered up the DC-DC converter, the charge controller for the accessory 12V battery was flashing that it was having trouble charging. I found the problem rather quickly. I had wired it in backwards! The battery was trying to charge the DC-DC converter, obviously failing to do so. Fortunately, no damage was done. After reversing, the unit appears to be charging the 12v battery properly. However, the charge controller, being only a 7A unit, seems to be on continuously even though no load other than the BMS is drawing from the battery. So, it's hard to establish that this circuit is charge limiting. At least I know the 12V pack, initially charged, was at 12.9V. I'll be measuring that voltage again later.

For now, the pack charger is removed when not in use. A mount will be constructed and the charger installed into it. After, it will be time to take the BugE out on it's first drive with the new pack.

On my BugE, all lighting plus the BMS is directly powered by the 12V battery. I did this since the battery safety cutoff circuit should stop all power being drawn from the pack including the DC-DC converter. That means in the event of a battery cutoff during a journey, not only would the BugE have no power, but it also would not be able to signal to other traffic that it had a problem!

I built my own wiring harness. The 12V system was built to be completely independent of the bottom of the BugE. That way, during assembly, I could just plug the + and - into the cowl lighting to test all lighting plus speedometer indicator lights without requiring the rest of the BugE to be present. Both cowl lighting and BMS run directly off a12V accessory battery (autocraft part#5L-BS). The size of the battery was picked due to it being on sale rather than being an optimal size. However, that battery size seems to work just fine. To charge the battery, I use a Sevcon DC-DC converter to feed into an ICP 7Amp solar charge controller. Not that either are optimal components. Both are much more expensive than are needed. However, to preserve the ability to go back to a lead-acid pack with no need for a supplemental accessory battery, I decided to keep the DC-DC converter arrangement as-is for now.

Post construction note:
If I were starting from scratch again, I would not muck about with a DC-DC converter at all. The weight savings isn't a big enough benefit. Instead, I would simply use a motorcycle battery with a separate 12v battery charger, mounted on the tail shelf where my DC-DC converter now sits.

Tuesday, June 14, 2011

Deciding pack orientation for lithium battery upgrade

When deciding how to install the batteries, it's useful to study photos. In the first photo is my setup for a lead-acid pack. Lifting up the rear, you'll see 4 Optima batteries plus Powercheq battery balancing modules on the shelf on the right. Note, the addition of a spatter shield wall that I made of fiber cloth with resin. I later added a rubber skirt for additional length plus a chain spatter shield. Since doing that, water has not been a problem for my BugE.

The next photo is from Allen Clark's installation. He decided to mount the lithium batteries to one side. This frees up some space for battery management electronics. In addition, I'm hoping I can fit a small 12V battery for emergency 12V accessory power. This would be needed in case the main pack goes into an unexpected shutdown while on a journey. If I was to use this configuration, the center hole in the front of the battery tray where the 12V harness goes through can not be used. Instead, a second hole would need to be drilled to the right. Fortunately, I left enough slack in the 12V wire harness that moving the pass-through location will not be a problem.

So, to check the arrangement of battery electronics and to avoid doing too much in a confined area, I decided to set up the lithium pack and electronics outside the BugE first. One issue I ran into was the inability of arranging a battery pack in series just by using the provided jumpers. I finally just made a cable to complete the series circuit (the brown cable on the bottom). The arrows trace how the jumpers make the cells into one big series circuit. The arrow path shows how the circuit begins at the (-) terminal and ends at the (+) terminal. Also, note the small stubby screwdriver on the lower left. When it comes to working on batteries, it's safety first! Either use a small stubby tool or at least wrap the metal stem of a regular screw driver with electric tape or heat-shrink so accidentally dropping it on the pack can't cause a short!

An alternate way of arranging batteries was suggested by Baka Nihao although his batteries are different in shape. The batteries in his tray are arranged in parallel and held in place for the season with "great stuff" insulating foam. I asked about battery management. He uses none. He also brought up an interesting point on having a separate 12V battery for lighting. If I was going to use a 12V battery for lighting and have it charge from from the main pack via a DC-DC converter, the battery will be in danger of being over charged.

Unlike Baka's setup, I have a 12V battery management system that will need continuous 12V power to balance cells in the large pack even if the pack needs to be shut down. So, I'm using an independent 12V motorcycle battery for powering the BMS. I'm going to try using a solar charge controller that I have left over from a previous project.

Saturday, June 4, 2011

The LiFeMnPO4 pack and BMS arrives. What next?

Note: This BMS system is no longer sold by Elite Power but it may still be available from other companies.

The batteries, charger and BMS came in two boxes. One was for the charger (large white box) and the other box had everything else in it. The batteries have removable purple covers. There is extra room in them. So, it's likely the tiny BMS boards can be installed under the covers to make the wiring look nice. Each set of four cells came pre-connected with metal bands on them (as shown in yellow box). Measuring the 4-pack gave a voltage of 13.1V .

Also with the BMS kit is a small LED bar graph display (middle black thing). Also, the vendor provided a free LCD display as well. The reason it's "free" is that it has a display defect. So it works, but looks ugly. Should I want to have a better looking one, I can purchase another one later. The BMS circuit boards came pre-wired, probably because I bought a "demo" system rather than a new one. On a new system, it's likely I would need to wire each board as I found it in the string.

So, this is the "big picture" of how the battery management system should go together.

Rick Suiter, my sales rep, emailed me instructions for a 24 cell model instead of a 16 cell model but I got the general idea. Like most things, these representative images are simpler than reality.

Since I need to make some decisions on mounting locations, I decided to lay out the components. The LED bar graph looks like it can be press-mounted into a rectangular space, perhaps somewhere on my polycarbonate dashboard. The "Control Unit" also has a mounting hole for a screw. However, the "hub" has no native way to mount it. So, I can mound it somewhere with double-back tape. Wire length may be the deciding factor on where things get mounted.

There were also some pieces that puzzled me. I got an assortment of additional metal pieces that I take to be conducting strips that work with the circuit boards. I'm also thinking having these strips will allow me to change the battery arrangement to have a wider or thinner pack.

There were also some flat to round adapters. They puzzled me. Why so many? They seem rather wimpy for a mechanical connection. However, wimpy they appear to be, Rick assured me that the parts would be sufficient for the job. Plus, he sent a photo too. He states below:

For #4 wire you can fold the edges around the cable and crimp it with a die size one or two larger. I've done this with 4ga wire and it seems to work well. See the attached picture. Soldering is an option, but there seems to be issues in a vibration intensive environment where the solder joints can fatigue and micro crack. If you did want to solder I would crimp first then back flow solder in to the wire, that way you are not relying on the solderto hold the connection, it is just there for extra conductivity.

The other mysteries had to do with recommended interlocks to prevent the pack from being damaged from too much discharge. Looking over my parts, I found I had a mysterious small heat-shrink covered component which was the reset switch. Since it was too small to be captured by my camera, I used Sketchup to doodle out an approximate image of what the component looks like. On each end are the letters "L" and "D". So, from the response below, the "D" was supposed to be an "O".

The little black piece with L and O on it is the low voltage cut off switch. ... The L side connects to the LIN hub, the O side is your output signal. You must provide a 12 volt and ground signal to the output side per the diagram, the middle wire is your switched signal for low voltage. I attached a document for the alarm cut out, it is for another version of the hardware, but the circuit on the last page will work to amplify the signal to drive a small relay directly if it is useful to you. Our warranty requires that the low voltage cut off be connected such that it disables the vehicle if a low voltage cell occurs.

Speaking of loads, in the diagram, there are two DC-DC converters. One small one seems to be for only powering the LIN hub with "control unit". This converter apparently remains on 24/7. The other is the high capacity 12V DC/DC converter for everything else. The larger converter appears to be able to talk to the LIN hub as well.

If a lithium cell either exceeds it's temperature or falls below a safe voltage, the BMS should "disable the vehicle" automatically. To do this, Rick offered the following suggestion.

In most cases the alarm switch signal will be used to drive a relay which will either break an enable signal to the vehicle main controller or break the power to a main contactor coil. Since the 5 milliamp signal is typically insufficient to directly drive a relay the below circuit can be used to amplify the output signal enough to drive a relay coil.

This circuit can be built with Radio Shack parts:

MOSFET IRF510 Transistor Catalog #: 276-2072
0.5-Amp SPST Reed Relay at 12VDC Catalog #: 275-233
1N4001 Micro 1A Diodes Catalog #: 276-1101
1M Ohm 1/4-Watt Carbon Film Resistor Catalog #: 271-1356

However, warranty or not, it's safety first. I don't have a problem with the traction motor loosing power if the pack reaches it's discharge state. However, if I'm gliding to the side of the road, my BugE needs hazard lights to warn the other drivers behind me that this BugE is goin' down!

So, how can I provide power to lights while the main pack recovers? Well, I need to re-think the decision of having a single DC-DC converter versus having a small 12V battery, charged with a 12v DC/DC converter. With Optima batteries, I think having a converter with no separate battery is the best approach. It's proven to be simple and effective. However, with a fussy lithium pack, a supplemental 12V battery is needed. So, this will require some changes to the wire harness to add a battery, charger, charge regulator and interlock. Then, there will be the challenge of finding a place on the BugE to mount a small motorcycle or gel cell battery. As they say, nothing is simple.

As for where to mount the other components, it looks like the LED bar graph could be mounted on the transparent dashboard where the existing 48V meter is. I could mount the larger LCD display on the dashboard as well. However, given the condition of my "free" display, it's likely I'll only use it for testing but not for everyday driving. So, I'll probably Velcro that display to the glove box area so it can be easily removed when not needed.

Sunday, May 15, 2011

From Lead to Lithium - trading simplicity for performance

I've decided to trade simplicity for performance. The lead-acid pack with battery management circuitry was very easy to maintain. Just plug in & charge. Lots of warning if the pack was being overdrawn and there was no need for temperature monitoring. They were durable batteries but they just don't give me the range I want. So, I ordered a set of higher-performance batteries plus a battery management system from Elite Power.

16 GBS-LFMP60AH LiFeMnPO4 - (4 banks, 60AH each)
1 BMS-16S battery manage system (no display)
1 EMC48-15 charger
With shipping, it all came to $2083.88 As a bonus, they did throw in a slightly damaged display. It's missing a couple LCD lines but it still has some use to it.

Even still, the whole system is quite a chunk of change! However, it will be worth it if it finally allows me to be able to use the BugE as a commuter vehicle. Over time, I hope to save enough gasoline to justify the cost of the pack. If gasoline prices stay where they are, that should not be too hard to do.

As a performance comparison, my real-world test range on a slightly damaged 2- year old lead pack was 12 miles with varying speeds & hills. Comfortable around-town range seems to be 10 miles one way. So, from the anecdotal evidence of lithium performance, I'm expecting an improvement in range due to...

1) not being damaged, unlike my present lead-acid pack
2) being somewhat lighter than the lead-acid pack
3) being able to use more of the capacity without damaging the pack
4) having more charge/discharge cycles before performance deteriorates

So, it's not beyond imagination to think I might be able to make the commute distance of 20 miles depending on how much energy I loose to wind resistance and hills. In order to do it, I'll need a re-charge at work for the return journey.

My journey will consist of roads that have rather easy slopes and allow me to drive at low speeds most of the time. All roads I've picked typically have good visibility and people are used to looking for roadway hazards such as deer or slow moving farm equipment. I have no doubt I could complete the journey at 20mph but be out of energy if entirely done at 50mph. So, the task is to find an acceptable mix of faster and slower speeds to allow the journey to happen in a reasonable amount of time.

Tuesday, April 19, 2011

The BugE returns to the roadways!

This time of year it's hard to predict the weather. A day might start out nice, then be rainy and cold. When this happens and I'm riding on my petrol motorbike, I go through an extensive 15 minute "dress up" and "dress down" procedure. Options include using chaps, rain suit, boots, additional layers of clothing, gloves with liners, earplugs, sunglasses (more for eye protection due to bugs than sun protection) and applications of RainX and NeverFog to my helmet visor. This is all needed to deal with rain, wind and noise that comes with riding a conventional motorbike. Today, thanks to an inaccurate weather report, I needed every bit of that protection to get home from work today. After the biker "fun" in dealing with all the wet gear after the trip, I realized I still needed to go to the monthly Green Drinks event I host in the area. However, it was still raining!

So, instead of taking my car, I decided to drive the BugE. The contrast between my earlier motorcycle ride could not have been greater. I just unplugged the BugE, put on a light jacket and was immediately on the road. No protective motorcycle accessories required (other than a helmet). Even with a steady 36 degree drizzle, I arrived at my destination neither cold nor wet. Nice!

Friday, January 7, 2011

Winterizing the BugE

Roadway salt is harsh on all vehicles. So, once the first salt carrying snowplow rumbled by my house, I decided BugE season was over. No special steps for winterizing were needed. Just park it in the corner of a garage with a battery maintainer plugged in and cancel the insurance. Cover it, check it once a month or so. Once spring arrives, I'm hoping all I need to do is re-insure & go!

Saturday, November 6, 2010

No news is good news

It's oil change day today. I do oil changes for every appliance all at once since it's often a messy operation. So, my regular car, regular motorcycle, lawn mower & snow blower all had their seasonal oil change. The BugE also was included in this operation. It needed a few oil drops on the chain. The other oil changes took much longer.

As it gets colder, I see fewer motorcycles on the road now and practically none are seen during cold rainy days. However, the BugE is just fine with that sort of weather. The BugE takes away the windchill and rain so it's a practical vehicle to use for cold weather driving. Due to the lack of wind and rain, the experience is similar to driving a car that hasn't had it's heater warm up yet. Practically the same since an across town trip usually isn't enough for a car to get warm anyway. Lack of windshield wipers isn't a problem. The lens stays remarkably clear of road spray (although I don't tend to tailgate other cars either). Even with the low temperatures, the batteries still have enough performance to go across town.

However, the BugE is not problem free. When parked in temperatures close to the dew point, the lens attracts fog (or ice if below freezing) Fortunately, it's not a problem while driving. Only when the BugE is parked. Parking in my garage eliminates this problem and it's usually not a problem with quick trips. However, it is a problem if the BugE is outside for several hours. Because of this, I now apply "never fog" to the inside of the lens with a microfiber cloth and I may try applying "rain-x" to the outside. Someday, if I truly get ambitious, I may try installing an electric Frost Fighter Kit .

Tuesday, September 14, 2010

New packs are available!

Alan M. Clark, one of the first BugE owners I had contact with, has upgraded his BugE with a lithium battery pack. He reports he's found a kit that fits in the BugE nicely and now gives him an incredible 42 mile test range! He also reports the BugE is now lighter in weight so acceleration is quicker and his stopping distance has been decreased as well!

I'm guessing a more realistic performance in my hilly area that would not stress the batteries would probably be 30mi @30mph or some combination of speed/range. As for overall value, lithium packs are more expensive but they should also have a longer service life than glass mat Optima batteries. So far, my pack suits my needs. However, when replacement time arrives, more people should have experience with these packs so it should be clearer if these packs really are as good as the specifications would suggest. I'm also hopeful that a recycling system will be made for these packs so the depleted lithium won't just be lost to landfills. For more information, check the link to the site HERE

Tuesday, August 17, 2010

My first official breakdown - a simple fix.

For the past week, the thumb throttle on the BugE has been acting rather touchy. Acceleration was more jumpy than I was used to. I was aware from the Google Groups that there were a batch of thumb throttles that were found to be bad. So, I really should have replaced it with a better control but it was a repair that was easy to put off. After all, it wasn't THAT bad.

Well, it turns out it was. After hosting a Green Drinks event, it was time to go home. So I pulled out, then had enough speed to go through a traffic light, then tried to accellerate more and...nothing! Fortunately, I had enough momentum that I could glide safely to a lit parking lot. At first, I thought maybe a lose spade connector was at fault. No such luck! The thumb throttle had finally failed. Since I didn't happen to have an extra throttle with me, I called AAA to have the BugE picked up by flatbed and brought to my house.

After putting the BugE away, I decided to upgrade to a nicer twist-grip throttle. I found a supplier on Ebay and had it delivered in three days. Then, I just attached the throttle to the handle bar with two screws, ran the cable to the speed controller, crimped on a couple of spade connectors, plugged them in and I'm done!

Although breakdowns are never fun, the fact my "auto-shop" is next to my house and labor is always free sort of makes up for it.

Tuesday, July 27, 2010

Laundry day with the BugE

My washer at home decided to start leaking. Unfortunately I don't have enough clothes to wear until my washer gets fixed. Fortunately, the BugE has ample cargo space for my laundry which can then be shuttled to the nearest laundromat. Just load up the BugE & go! Believe it or not, all my weekly laundry (minus the hamper) can fit in that cargo space. It's bigger than it looks!

Friday, May 28, 2010

Usage observations

So far, my BugE has been pretty well behaved. My suspension upgrade of lifters & frame sliders continues to give a very smooth ride in spite of potholes and railroad tracks. I've done round-trips to all 4 corners of my town and have demonstrated that I can still be in the upper green of my charge meter when I do it. I do need to "think" while driving as I do on a motorcycle since the BugE is a small vehicle among giants. However, I don't have a problem keeping up with in-town 30-40mph traffic. I still get more waves and smiles per mile than any other car except perhaps an ice-cream truck. I'm also starting to realize some nice cost savings by using this as my town runabout instead of my car. No gasoline, no oil, no exhaust system, no coolant, no transmission fluid, no "check-engine" light. I also really like the ability to carry stuff easier than I can on a motorcycle. Also, I don't need to dress in a rain suit when I just need to go on a simple errand. Trip after trip, the BugE is able to get me there and back.

As for the fear of "running out" of electricity, it's not really a problem. Driving the BugE is kind of like driving a horse. Gradual speedup gives much better range than doing full speed sprints. Just like a horse, the BugE will last longer if not being driven as hard. If the BugE is "tired" (meaning the meter is going into the lower green zone) let it rest. Parking for even 10 minutes will let the batteries get most of their performance back. Then, when I go back home, I need to plug it in to "feed" it.

Monday, May 3, 2010

So, what the heck happened?

Got the motor back via UPS. I also talked to the person who repaired the motor. I found out my motor was not damaged by water. Instead, one of two things may have happened. First, there may have been a factory defect in the "core" piece of the motor. Second, the "core" may have failed due to driving habits. Turns out, if a motor has lots of current but can't move (maybe it's on a hill) then the windings can overheat. When that happens, some windings might short and the commutator can warp too.

So, to play it safe with the motor, I have changed my driving habits a bit. First, I avoid "flooring" the throttle just to show off, especially when going up steep hills. I find cruising at 30MPH keeps up with traffic yet doesn't lose too much energy due to wind resistance. Since doing these simple changes, I've discovered my range across town has increased dramatically.

Thursday, April 15, 2010

Top speed mystery solved.

For the last few trips, I figured my lower top speed was due to a damaged battery in my pack. However, I noticed even if I totally opened up the throttle, the batteries would dip a little but still stay in the upper green. So I figured something else must be wrong. On the last few trips, I would think I would smell something that seemed electrical or possibly a dragging brake but I could never pinpoint it. Then, today, when in a 40mph zone, I noticed I could not get above 30 on flat roadway with the throttle wide open and still in the green!

When I got home, I Immediately inspected the BugE to see if I could pinpoint the problem. The rear parking brake was cool. The front brakes were warm as expected but not excessively hot. The splash plate had come undone and was rubbing against the tire but that would not possibly be enough to slow the BugE down that much. The motor controller was cool too.

Finally, I inspected the motor. Very hot! At first, I thought the chain may have been miss-aligned. It had a little slack in it but it looked OK and had plenty of grease on it. The sprocket teeth also looked OK too. So, I re-aligned the rear tire, tensioned the chain and took it for another test drive around the block. Same thing - poor top speed and the motor heated up again. Normally, the motor runs cool so this was very unusual. The last symptom was that that the motor now makes a sound similar to what I thought was a miss-aligned chain drive. However, when I took off the drive chain, I noticed the sound was still present! It was quite a bit different from the "Boba-Fett" whine it normally makes when underway.

I then decided to take the end motor cover off to check the brushes. No signs of rust and it was not terribly dirty. What I did find was a very uneven commutator pickup with lots of carbon on it and an end bearing that did not turn very well. When operating, the brushes were bouncing up and down quite a bit! That apparently was where the "chain sound" was coming from.

So, I contacted the Advanced DC motor people. They recommended a motor shop relatively near where I live. Since the motor is more than two years old, this problem isn't covered by the manufacturer. However, the repair place I took it to replaced the whole "core" and gave me a new 6 month warranty. Although it was no fun paying for that, there was one bright spot. Unlike a car or even a street motorcycle, it was easy for me to extract my motor and bring it to the repair shop myself.

Saturday, March 27, 2010

Works better if I plug it in.

Turns out my charger was in trickle charge mode. 2a@12v. That charge, split between 4 batteries (with the powercheq mods) is not a lot of power to replenish the pack. That suggests the batteries may have simply been under charged on my second set of trips. So, i suspect I had the volts, but not the amps. However, waiting for a full charge has restored the pack.

The adventure into the 12v/powercheq way of charging is just a temporary measure. When my 48v side charger failed (from dropping one too many times) I thought about just getting another to replace it. The problem is, they are over $150! Instead, I'll be trying (4) Black-and-decker 12v-2a mini chargers. These don't charge up fast but four of these are less expensive than another 48v charger. They should also balance the pack when charging. Charging at 8AH, it would take 27.5hours to completely replenish the theoretical 220AH capacity of the pack. However, I don't anticipate drawing down the pack that far. If I drive moderately, I should be OK with overnight charging. Not that this will make a huge difference in my electric bill. The whole charging system will use in the neighborhood of 96W. So, I expect the charging cost on my utility bill would be approximately like leaving my porch light on all night.

The chargers could be mounted in the battery pan or on a shelf similar to the ones in this photo. Why use this particular Black and Decker kit? Each charger outputs 2A (versus normal 1A that most battery maintaners output). Plus, they come with all the cords shown which would save the trouble of putting on molex disconnects for future maintenance. These charger kits are available for $19.95 ea. (plus $4 shipping) from Tyler Tools.

Thursday, March 25, 2010

Water Bug!

It's been raining quite a bit. So, I again decided to see how the BugE would do. It is very convenient!

The Good. The cowl protects against windchill and rain REALLY WELL on rainy days. Much better than it's shape would suggest. I have not needed gloves nor chaps. Just wearing a sensible coat allows me to arrive warm and dry - even in 35 degree rainy weather! The front brakes work BETTER in the rain. That was handy for two panic stops I did! As for visibility, the "road film" on a car windshields does not seem to be forming on the BugE canopy. A bird did poo on it. However some water/vinegar mix and a microfiber cloth removed it off just fine! On a rainy day, I just take the BugE out of the cycle shelter, unplug it, put on helmet, get in and go! (note, if unplugging in rain, outlet should be GFI) Also, now that people in town have seen it in action, I don't get stopped as often by people with questions.

The Bad. I unfortunately when I constructed it, I didn't seal the cargo area well enough so rain collected in the cargo area. For now, I just drilled a hole in the bottom to let the water flow out but I'll be putting a better seal around the door. Also, the foot well is collecting water from my wet shoes however two small drain holes can take care of that. Also, I've noticed potholes around town are quite large so I need to pay attention to road conditions much more than I would in a 4-wheel car.

The Ugly. Today, I used the BugE for three round trips downtown at rather slow speed (15-20mph). Each round trip was around two miles each (although, I will say, these trips DO have some hills which may be why range seems so low). I did opportunity charge at home, but apparently not enough. On the last leg of the 3rd trip, the needle again went completely limp when my throttle was applied going up the final hill. So, this time, I pulled over and waited a few minutes. The pack recovered enough to make the hill and get me home again. I later found that I hadn't left home with a full charge since it was set to trickle charge mode instead of full charge.

Originally, I charged with a 48V external charger. However, it was dropped one too many times so it doesn't work. So, I'm now charging with an automotive 12V charger and relying on the powercheq modules to even out the charging. I'll eventually be installing 4 individual low profile 2A-12V on board chargers instead of one big charger. Now I know the terrain limits around my area, I should be able to drive without running into range problems.

Sunday, March 21, 2010

A test of it's range - lead-acid pack

40 degrees, sunny. It would be a cold day for a regular biker but the BugE protects against windchill so there was no need for gloves or chaps. Just regular street clothing & a helmet.

So, I started out.

2.6 miles from home to walmart, the streets were stop & go for 3 stop signs, then 40mph down a hilly boulevard. Kept up with traffic and even passed a few cars :) I stopped for around 10 minutes, got groceries. Then decided to visit the park. It's 3.8 miles from Walmart. To get there, 40mph down boulevard again, full throttle to climb a hill, then more stop-go back street driving. The majority of the journey, I maintained 30mph with light traffic. When I got there, I decided instead of stopping at the park, I would head home - which I realized was now around 3 miles away on a slight uphill grade! So, the return speed was kept to 28mph, then I slowed to 25mph with needle creeping lower each time as throttle was applied. By the last mile, the needle was completely limp when throttle was applied but I managed to maintain 15mph through downtown where I knew speeds could stay slow. I almost pulled over to let the batteries recover but parking wasn't favorable to that plan. What was really disturbing was in the last 1000 feet when the controller started to turn off, then on. I managed to make it home & do a last climb up the driveway.

I noticed at the last two stops, that turning the headlight off at traffic lights (but not brake light or turn signals) helped the needle creep back into the green zone until it went limp again when the throttle was used.

So, there it is, a variety of driving. I can't say I'm thrilled with the experience of my last mile but "resting" the pack and opportunity charging should allow me to safely stay under this tested range.

My Optimas D45s are now two years old (bought in spring of 2008) and they would spend months not connected to a charger during construction and refits. Plus, there was the shorting incident which took away even more performance. Since shorting two of the batteries, I've no longer been able to reach over 50mph even down hill with that pack. So, I did not expect full performance.

Thursday, March 18, 2010

BugE - now road legal in New York!

Finally, FINALLY, after all this time, I managed to get a plate from the NY-DMV!

I decided to take the BugE for an across town trip. OMG! This thing is fun! At first, I was a bit conservative on my route, only going along back roads. However, after getting used to how the vehicle worked, I was soon flying down the main strip with no problems keeping up with traffic! Acceleration remained good through the journey and battery life was much better than expected (probably due to the powercheq modules). I criss-crossed from one side of town to the other and was still safely in the upper part of the green zone when I returned. Both suspension changes work great - even over railroad tracks! Clear skies, nice sunset. Truly a fun ride! I ended the ride with a well earned beer at the local bar.

However, it has all been a bitter-sweet experience. Thanks to New York State, this simple vehicle became needlessly expensive in terms of up-front money and time. Paying sales tax on my own home-built vehicle made of retail parts was a final insult. However, it's over. Now, I just pay motorcycle rates for registration, inspection and insurance (just over $200 for the year). Of course, I also don't need to buy gas either - just occasional batteries. If I go for a different battery technology such as nickel iron, I may not even need to do that again either! Repairs of course are now very affordable and hopefully infrequent too. If I were to use my 200W solar array, it would even be Fusion powered!

So, I've gotta say, after a long journey, the future has arrived!