We disassembled the primary failed pack. It had zero volts on it and showed a short from the leads to the aluminum case. We unfortunately do not have enough experience in the field to discern any knowledge from the results. It obviously got hot, vented, smells (lithium), burnt through its case into the module below it. The module below also shows a short from one terminal to the case, it still has 4 volts on each series of cells therefore 8V across the module. The module above the failed module shows no damage externally, but is at zero volts. We are open to suggestions on how we are supposed to dispose of the modules.
VW 2003 Golf GL 2.0L conversion to an Electric Vehicle.
Saturday, December 9, 2023
More images of Exothermic event.
Wednesday, November 22, 2023
We had an exothermic event.
The pack voltage suddenly dropped and two of the rear pack cells read zero volts. What is that lithium smell?
Full pack view, find the tip of the blue arrow.This is the rear pack, showing 20 of the 26 modules in the rear pack.
The third and fourth in the stack welded together.
We had an issue while removing the rear pack. To remove the rear pack from under the car where the gas tank had been you need to disconnect the electrical and BMS leads from the car. We built the pack with long conduit pigtails such that there are no connectors under the car to leak or get damaged. We then also place a solenoid in the pack housing to cut off the positive side of the battery from even the pigtail as an added precaution. We were told that was over kill. When removing the "dead" negative lead from the front of car connection we noted, "I think my finger is tingling?" " Can't be, the main fuses are pulled and the positive lead is disconnected." "OK, lets check with a meter." "The meter says nothing from POS to that connection, must be your finger." We finished removing the bolt and started to pull the cable from the housing, POW. Arc from the cable end (Which now needs to be replaced) to the battery case. "What the %#@^"
There was 110V from the cable to the chassis of the car. Is the POS solenoid stuck? No. BMS wires shorted? No. Main NEG cable crossed a bolt in the pack? No. One of the bus bars in the pack came loose? No. ..... When the battery failed, it internally shorted the entire rear pack to the chassis of the car! We did not know these batteries could fail this way, Thus it is imperative that a full system fuse be placed as close to the battery output terminals as possible. We got lucky as the method in which this system failed had no fuse in the failure path, all the fuses were placed up at the front of the car and after the pigtails for ease of accessibility.
The entirety of the failure was contained in the rear pack housing. There was much rejoicing.
Thursday, June 16, 2022
Rollin' Rollin' Rollin'
Since it is running, it spends more time running than being worked on. Recent work has been:
- Get the tablet to display the outputs again. We made a change to the main computer such that it will not look for and read in code from the SD card unless we hold a button down. This makes the system boot almost instantly and avoids the poor connection issue during cold months preventing the car fro starting. The caveat is that since the computer is not reading from the card where all the HTML is stored, it would not broadcast the readouts. Solution was to load the HTML to the tablet directly which turned out to be a challenge in itself but is now complete and working.
- Working to get the Nissan Leaf Gen II BMS to output the battery voltages on the CAN system. We have still not successfully completed this step anyone in the area that knows how to get the output is welcome to chime in. Once we can get the output from the BMS, we can automate the charging process.
- Crossing 6000 miles on the road.
Wednesday, February 9, 2022
On the road again...
Over winter break we were able to install the new battery modules, check the wiring, and put is all back together.
To check the wiring we got a couple of boards from Janosch Oppermann.
The X and ! represent Nissan splits in the pack that do not light.
While the battery was out we took the opportunity to weld in the rear seat pan, seal, sound proof, and paint it.
Next task, back to trying to read the BMS output so we can implement unsupervised charging.
Friday, November 19, 2021
We have spent months finding replacement parts.
Saturday, June 26, 2021
One year forward, three years back.
You may have read in the previous post that the BMS seems to have blown a chip, we still have not figured out what is going wrong, but now we consider ourselves very lucky. Let this be a WARNING for all of us, plug in your BMS AND check that it is actually working. We have TWO completely shorted out cells sitting at zero volts.
The bottom two modules of the inner stack read ZERO volts. These represent the center modules 12 and 13 in the leaf pack, they usually have the main disconnect between them.
Thursday, June 10, 2021
We have been working on programming the charging system.
To date we have been running the Brusa NLG513 charger in manual mode limiting the pack voltage to 388V, sacrificing some range for charging safety. We recently have been working on the programming to read the individual cell voltages through the Nissan BMS such that we could turn the Brusa charging parameters on/off, amperage up/down as the pack charged. We have been having one heck of a time getting the data out of the BMS. And now we know why.
We think this is a 2013 BMS, but the wiring from a 2012 is every so slightly different. If anyone has a table from Nissan to confirm which diagram we should be following? If anyone has a new/used version of this same BMS to share with the project?
Summer 2021 update
We made it through the winter.
Since the car is kept inside, the heated seats were plenty to make it winter driveable as we did not need to scrape the windows.
Cruise control is up and functional on the original VW cruise stalk. Works just like the original car but better. Set and Cancel as expected, brake tap cancel as expected, + now gives 5mph increase like new VW models. Tap the accel pedal to cancel and engage regen as expected.
The radio has had a $6 Bluetooth receiver added inside it, place a CD in the player that is one 67 minute blank track, the CD player turns on, the 5v logic in the CD player turns on the BT chip which then seeks the kids phone and they can stream music via the CD audio inputs overplaying the blank playing disc. I think the idea and implementation are very slick although I do not approve of phone use while driving.
Extra bonus, we have taken this technique and applied it to two OLD VW's and without Android Auto the GPS directions play in my car via the speakers. GREAT!
A bent tierod and groaning front right wheel bearing have been replaced.
The headlights have been re-aimed accounting for the added rear battery weight.
The too dark window tint from the previous owner has been negotiated. We removed the lower half of the tint on the front windows. Lots of discussion happened here, I think it looks fine and works great providing sunshade while driving AND allowing clear view to the side mirrors and side of vehicle. Others think it looks less than fine. Function before form.
The transmission linkage rod lengths have been adjusted per VW specs after a bit of difficulty getting into reverse and second gear. problem solved.
The VW computer harness has been re-wrapped minus all the engine management wires. We attempted to output a pulse-train from the new computer into the VW ECM such that the motor RPM would appear on the dashboard RPM gauge, we found that the VW ECM was smarter than us and recognizes the other engine inputs are not correct and then shuts off the RPM gauge output. So until we input directly to the gauge motor we will not have RPMs in the dash. Either way we have come to the conclusion that 2nd is good for in town and up to 55mph, on the highway we use 3rd.
Going into this project we wanted to know why the Big 3 did not produce an electric. We did not know if we would ever complete, but we figured we would learn a lot along the way. The conclusion we have come to is, electric is completely viable for ALL sizes of city commuting, with continued battery development and a SLIGHT shift of travel mentality fossil fuel vehicles should go by the wayside for ALL daily family uses and many work uses too. Long family vacations should consider rental fleet vehicles, or more rest stops at interesting places for an hour or two along the way.
All told we have spent ~$9000 including the vehicle on this project and have come away with a daily driver, several college diplomas, and great offers to enter industry for the graduates. I deem this project not quite complete yet as the charging circuit needs a bit more programming, but overall a success.
What's next?
Friday, October 30, 2020
It is getting colder here.
The temp dropped near freezing one night while the car was out. The battery did not have enough to get home. We limped to a friends house that happen to have two electric cars, neither of his chargers worked with our charger. If anyone is familiar with what it takes to get a Brusa NLG513 to work with public chargers we could use the help. We got the regular charge cable and wired it directly to the circuit panel and were able to charge through a metered connection. We charged 20kWh into the pack.
We have now ordered another J1772 plug to place a regular 110V plug on. We have found our split 110V socket system does not work on any GFCI circuit and therefore is far less useful than anticipated.
Priorities change when your cold. The donor GTI is providing parts again. HEATED SEATS. Very little modification has been needed to mount the controls directly into the seat fronts to reduce wiring in the chassis. All we need is 12V and ground up into the seat, since the fuel pump is not used anymore and the wires pass along the seat rail that is the likely power source as it is independently fused and relayed.
The GTI did not use seat belt closed switches but our car did, so with the easy removal and replacement of one bolt the wired seat belts are still in the car.
Seat heat dial installed in the lower front of the seat. They light up too. |
Not to worry, the wire nest was cleaned up, wrapped up, and clip into position. The rails were also cleaned and lubed. |
Wednesday, September 9, 2020
Driving
Many 100's of miles are on the system now, we regularly go 50+ miles on trips but tend to chicken out beyond that. We have had one 78.7 mile trip to a farm house in the middle of nowhere and waited for an eight mile tow home. This was before regen was working. Now that the charger is running as expected we may venture closer to the edges of the battery voltages. We have been only using the middle 60%.
Confidence in the car is growing and it regularly leaves the city proper for excursions to other nearby cities.
Cruise control is high on the list of things to get functioning. We purposely turn regen off during higher speeds as we note that the neutral band in the accelerator pedal is not wide enough and we can see the regen fluctuating in and out reducing efficiency in cruising.
Steering
We have not decided that we need power steering. While maneuvering into a parking space requires more effort, at any rolling pace the feel is normal.
Rather than dead head the power rack hydraulic connections, we have reinstalled the steering hose lines looped back onto themselves including the one way valve in the inlet. This should cause the fluid to circulate through the entire system as we drive normally.
Charging update
We have struggled with public charging, and have not had success at a public charger yet, but we have been able to charge at other peoples homes setup with chargers.
We have learned that in the image taken from Wiki J1772 interface:
Hi,
I think you have done everything right basically, ... What you probably didn’t know (and which is not described clearly I admit) is that the "SDT Batt VoltHi: ERR" is produced by a crowbar like circuitry, which measures output voltage very fast but not very accurately. This is intended to avoid damage to attached circuitry in case the battery suddenly disconnects and causes a load drop to the charger. The resulting voltage overswing might damage sensitive electronics like DCDC-converters, amp-hour counters etc., so it must be avoided by fast shutdown of the power stage.
Now: As I said, this fast measurement circuit is neither precise nor is it well filtered, so any peak / disturbance / noise etc will trigger the shutdown and throw the error.
The value which controls this crowbar/shutdown circuitry is the second value in the orange/yellow fields, which says «switch off immediately if Battery voltage above [V]»
And this value is set to 390V in your case, which is very close to the 384V you intend to reach. So remedy is pretty easy: Add a healthy headroom to the «switch off immediately if Battery voltage above [V]» value, let’s say you set the limit to 460V, and you’re done. Required headroom depends on various influencing parameters, however with a margin of 20% you’ll probably never see any nuisance tripping of this crowbar again.
We changed the value to 403V, =4.2*96 the highest the cells want to see. The system works now.
Thursday, August 6, 2020
Brusa NLG 513
We are using a J1772 connector. We need to tell the charging station to turn on and give us at least 16 amps at 220VAC. The on-board Brusa NLG513 will regulate the charge from that point forward in conjunction with the Nissan BMS and DMOC adapter.
Currently we are using the Brusa in manual mode until all the CAN communications are established.
Taken straight from Wiki
Connections to charger |
Friday, June 26, 2020
More on the proper application of a DC-dc convertor
Our learnings suggest that if the DC-dc is connected straight to the battery at 12.xV charge, the DC-dc will output as much as it can to bring the battery up to 13.2V instantaneously.
As is today. Circuit below is shown same as above, but needs to be changed for the wanted operation. An on-board DC-dc RV charger has been suggested. Other suggestions? |
Second out of town drive
Lessons learned:
- Regen ON causes far more heat build up than with Regen turned off. Regen is when the energy from slowing the car down is reabsorbed through the motor and placed back in the battery system for reuse.
- The accelerator pedal is setup such that the first 1/4 of the pedal travel is Regen, and then Acceleration. There is enough regen capability that the actual brake system does not need to be used in regular driving. FYI, the Regen system activation does cause the brake lights to turn on.
- We need more cooling; it is not clear yet whether the pump is not pumping, if there is a blockage in the lines, if the system has an air bubble, if we need the fan on the radiator blowing, or if we just need a larger pump. Regen is off until we figure this out.
More control relays
Wednesday, June 10, 2020
BANG SSsssss
Tuesday, May 5, 2020
DC-DC converter installation and update
Sunday, May 3, 2020
Charge anywhere?
Weight and balance of eGolf
Actual eGolf numbers"
Measured weights no fuel
Borrowed some digital scales.
Lbs L R 2674
F 897 750 147 62%
R 502 525 -23 38%
Difference 395 225
52% 48%
W/153lb Driver L R 2827
F 953 774 179 61%
R 555 545 10 39%
Difference 398 229
53% 47%
Best current guess is the car will gain 500lbs to 3200 lbs total w/o the driver. Most of the weight gain would be in front of the rear wheels under the rear seat with batteries.
EV version guesses
Lbs L R 3174
F 897 850 47 55%
R 702 725 -23 45%
195 125
50% 50%
"
Lbs L R 3076
F 965 917 48 61%
R 575 620 -45 38%
390 297
50% 50%
Original weight 2674lbs+ 15 gallons fuel (90) = 2764lbs
eGolf weight 3076lbs
weight gain = 312 lbs gain.
Thursday, April 16, 2020
DC-DC converter bought
Car OFF: no resolution
Ignition ON: Spike, 10A : Steady state, 4.5A
+DRL's ON: Steady State 20A
All things on that can be controlled: Spike, 80A : Steady State, 50A
Therefore minimum 450W, Steady max: 600W, Spikes: 1000W
Vicor provides two current options, the 3623 and 4623 chips. The chips can be had on evaluation boards.
Two of either board would be needed. Available from Vicor for $1610. Or Digikey for $1323.
eBay was scanned for alternate options. It was found that old Vicor PFC Mini, Maxi, and Mega power converters could be applicable but less efficient. On the Mini versions the outputs are usually printed directly on the main sticker, but on the Mega units the main sticker does not tell about the outputs and unfortunately most retailers do not seem to recognize that the numbers are on the individual modules and require closer pictures to identify the many different outputs. Eight outfits were contacted to collect the output information. Five of the stores responded with the identical ?stock? answer "Thank you for your inquiry. A picture of the sticker with all of the information is in the listing. If you are interested, please make an offer via eBay and we will review it. If you have any other questions or concerns, please advise. Thank you and have a nice day."
Thanks to:
An eBay Store |
Alternately a used Vicor PFC Mini PM1-03-576 was found on eBay.
It is rated at: Input, 115-230Vac 10A: Output, 12V/99.9A
Despite these being listed as A/C input, the user guide specifically says they are rated up to 380Vdc input. Their output capability is 600W/module but derated in the pack to 500W/module allowing 1500W max output as the -03- designates this unit has 3 modules in parallel. You can see the bus bars connecting the three modules in the above image. The Output voltage can also be adjusted between 8 and 15V.
Tuesday, March 31, 2020
VIDEO
"C" Programmers out there?
We have 5 computers to connect via CAN: Nissan BMS, VW car, Azure DMOC, Brusa charger, Wolftronix adapter.
If you have time and willingness to read some documentation we can use help programming the adapter to be the communication hub for the 4 other systems.
Monday, March 30, 2020
AND
Monday, March 23, 2020
Computers
Wednesday, March 18, 2020
Looking for a sounding board
We are looking for anyone in the Champaign County Illinois area that has sound logic and familiarity with Nissan, VW, electric car systems that is willing to sit with us as we walk through the system before turning it on?
2020
All the 2020 posts have disappeared.
So the quick update is that we think we are within days of getting it to roll under its own power!
Let's try and catch you up, the order may be a little out of actual sequence.
(Looking down just behind the firewall up in the windshield wiper area where the old car ECM is.)
Right in the center you can see a bundle of wire connecting to the left connector on the old ECM. Adjacent to the right of it we have been able to remove the entire second wire bundle as it controlled the old engine. You can see in another photo below some of the error lights caused. This bundle will be wrapped back up soon as we figure out how to fake the old codes.
Most of the old car systems are back up and running including the ABS, and Airbags without change.
The BMS (orange center) harnesses have been connected and the Nissan Leaf BMS is completely connected now (lower left in glass case under wire bundle).
Top just to right of brake fluid reservoir are the relays that ran the old car emissions systems, they will now run the new computers and DC-DC converter.
Hole just above the old main battery will be the location of the DC-DC converter (was the old engine intake airbox).
New recessed battery covers (white) in place, they will be clear before being sealed down (white plastic coating will be removed).
Under dash, looks like a regular car, counting left to right, 3 red wires, then a black wrapped blue wire, just above it is the VW fuel pump relay (black with white circuit diagram printed on it). This will power the new systems relays. IF the airbags deploy, it should automatically disable the new systems and disconnect the main battery power. |
More images of Exothermic event.
We disassembled the primary failed pack. It had zero volts on it and showed a short from the leads to the aluminum case. We unfortunately...
-
The temp dropped near freezing one night while the car was out. The battery did not have enough to get home. We limped to a friends house ...
-
Since it is running, it spends more time running than being worked on. Recent work has been: Get the tablet to display the outputs again. ...
-
A friendly voice in CA suggested a blog would provide good easy documentation and a way to get feedback before we make a bad choice. Please...