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Discussion Starter · #1 · (Edited)
Hi guys,

I thought I start a thread about my journey with the high voltage battery. Please note: If you are not experienced, please don't work on your high voltage battery. It can cause serious health damage and can even kill you. So if you are not sure if you should work on the battery: Don't do it. Also, I won't show how to work on the modules when connected.
In addition I got help from a friend who is professionally working with batteries.
Please excuse any language mistakes...I am from Germany ;).

How it started:
I purchased my Fisker in Jan 2018. Right from the start the range was not as it should have been. When I brought the range down to 17km the range dropped down to 0 immediately. Besides that everything worked fine. Didn't bother me too much so I drove 28k KM with the car until a few months ago.
However, at some point in time it started to get worse. I charged the car, full range appeared on the screen but after 500 meters the range dropped down to zero and the engine kicked in. During driving sometimes range increased from 0 to some kilometers but immediately dropped down again.
Conclusion: Serious issues with the HV battery. Unfortunately I don't have Fisker sync or Prodis at hand to find out the faulty modules, so what to do? I read a lot here on fiskerbuzz and also reached out to Jim Roush from Roush Restorations (a.k.a. Fixsker here on Fiskerbuzz). I cannot stress enough how much help he provided. Even though it was clear from the start that he won't make any money out of it as shipping of the modules to Germany was not possible. Thanks Jim, really appreciate all your effort.
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Ok, so, I put the car on the lift, pulled the battery out and disconnected the modules. As a start I checked the voltage of all modules, hoping that one or two of the modules would be significantly lower than the others (like maybe 3V...).
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Of course I got disappointed:
M1: 24,25V
M2: 24,32V
M3: 24,29V
M4: 24,22V
M5: 24,32V
M6: 24,30V
M7: 24,30V
M8: 24,32V
M9: 24,32V
M10: 24,31V
M11: 24,29V
M12: 24,31V
M13: 24,30V
M14: 24,27V
M15: 24,13V

What to do now? What you really want to know is how the modules/cells react under load. If you think about it, it makes sense from two perspectives:
a) The car shows full range but drops to Zero when you drive (under load)
b) All voltages of the modules are close to each other (no load)

Maybe a few cells show full voltage but will break down under load? I took module 15 (the lowest one) as a start and removed the lid to get access to the cells. Each module contains 21 cells, 3 of the cells form one "pack of three", connected to each other in parallel, which means there are 7 "packs of three" in every module with a serial connection.

My friend got a tester (basically a box with a heat wire to "burn" engery") which operates at around 12V and can pull 40a. We started with half of the cells, connected the tester and checked with a measuring device each pack. Et voila: Under load one of the "packs of three" dropped immediately from 3,3V to 2,5V. All the others slowely decreased from 3,3V to 3,29V, 3,28V....and stabilized at 3,10V.
There we go, we were able to identify the first defective "pack of three" in module 15!

Checking every pack in the module is very time consuming...there must be a way to be more efficient.
More to come next week 馃憢馃憢

Best,
Fabi
 

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Discussion Starter · #2 · (Edited)
Hi all,

a little status update. Last week we identified one defective cell in module 15. It has been very time consuming to check all cells with the tester so we thought about how to test all modules at once and we came up with the solution below:
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It's basically a little tester on a wooden plate with contacts. The little tester can identify the delta between the highest and the lowest cells. Which means if you put the module under load and one cell is defective, the delta will increase immediately. So, increase of efficiency but still not the best solution as you have to remove the lid of every module. So why not use the plug? The car is able to balance the cells which means there must be a connection to every cell via the plug.
As a next step I identified every cable from the plug to every cell. The blue cables are the temp sensors, the black ones are for balancing.
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Next challenge: how to use the plug? I had to find a socket to connect with the plug. I measured the distance between the pins, it's basically very common: 2,54mm and there are 18 pins.
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Searched the internet but the plug seems very unique, didn't find a socket. But I found a cable for computers with 18 Pins and the correct distance:
Product Rectangle Automotive lighting Font Violet

Ordered it via Amazon and identified the cables for each pin. You need 8 cables to balance the 7s modules.
Also, I got my hands on a used Junsi iCharger 308 duo which is able to charge and balance two 7s packs at once. I connected the balancing cables from the iCharger to the cable with the plug. And guess what: it worked :)
 

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Discussion Starter · #3 · (Edited)
With that cable, we were now able to identify the status of every cell while putting them under load. A lot of testing now...but, good news: it seems like it's only module 15 which is defective! I send an email to Tomas in Lithuania. Unfortunately I couldn't purchase any modules from Jim, because we had no idea how to ship them. I would have loved buying from him because he helped me a lot, but still...not possible. Tomas was also helpful and the module is currently on its way to my place.

In the meantime I charged and balanced every module with the iCharger and the cable. The charger was able to charge and balance every module. So again, good news :cool:
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More to come when the new module arrives!

Best,
Fabi
 

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(This is Jim) Good work Fab! Nice write up. If anyone in North America needs support, needs replacement Modules, or wants their pack rebuilt, you can find us at roushrestorations.com. Glad you got it going Fab! Stay safe!
 

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Discussion Starter · #5 ·
Thanks Jim!
Just a little update today: the new module arrived on Monday so I drove to the garage on Tuesday. Did a little testing, the module seems fine. Also, I checked the status of every cell in the modules again. I charged and balanced all cells a few days before Tuesday and I wanted to know if the delta on the cells increased in the meantime. Good news: all modules have a delta around 8-12 mV between the cells besides one module where the delta is 23mV. I think I can live with that but initiated another balancing cycle for that module.
So, all set now. I will put the car back together on Saturday, change engine oil and hope for the best :cool:.
Best,
Fabi
 

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2012 Fisker Karma #1030
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(This is Jim) Good work Fab! Nice write up. If anyone in North America needs support, needs replacement Modules, or wants their pack rebuilt, you can find us at roushrestorations.com. Glad you got it going Fab! Stay safe!
Please (please) stay in business - I'm sure you're going to get a lot of business in the coming years,,,
 

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2012 Fisker Karma #1030
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Thanks Jim!
Just a little update today: the new module arrived on Monday so I drove to the garage on Tuesday. Did a little testing, the module seems fine. Also, I checked the status of every cell in the modules again. I charged and balanced all cells a few days before Tuesday and I wanted to know if the delta on the cells increased in the meantime. Good news: all modules have a delta around 8-12 mV between the cells besides one module where the delta is 23mV. I think I can live with that but initiated another balancing cycle for that module.
So, all set now. I will put the car back together on Saturday, change engine oil and hope for the best :cool:.
Best,
Fabi
Wuenscht dir viel Glueck! Bin gespannt wie es ausgeht!

Good luck! Eager to learn how it goes!
 

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Discussion Starter · #8 ·
Hi guys,
just a little update: HV battery is back in the car again! But...car does not move :cautious:. It's showing "HV fault" in the display and blinking ready:
Speedometer Motor vehicle Trip computer Tachometer Gauge

Range etc. is there so the car is definitely aware of the battery. I am only able to shift to P and N.
I think I made a mistake when putting the car back together, I connected 12V battery first and MSD later. I assume that's what caused the fault code. Deconnecting both didn't do the trick :(. Seems like I really need a Fisker Scanner to check what's going on.
Is anyone aware of a scanner in Germany?

Best,
Fabi
 

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Time for a Diagnostic trouble code reset! Only possible with a KarmaSync or Prodis computer. I am unaware of any other process to clear out those codes and check for other fault issues.
 

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Discussion Starter · #10 ·
...I can't believe it's 20 days now but guess what: we are back on the road 馃!
A former Fisker mechanic (Angelo) visited me on Saturday, plugged in his laptop and diagnosed an issue with the HV bus-line. He pulled a new MSD out of his bag, plugged it in et voila: car is running again! I didn't have any issues with the MSD before, no idea why it went bad now. But hey, I was pretty happy that we didn't have to pull out the battery again 馃槄.
He also did the airbag recall and software update to 535.
Seems like we did a good job in changing the modules/balancing 馃檪.
Best,
Fabi
 
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