Volt Gen2 battery using Volt Gen1 BMS

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arber333
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Volt Gen2 battery using Volt Gen1 BMS

Post by arber333 »

As i stated in this title i intend to use Volt Gen2 battery and make wiring interface to use Volt Gen1 BMS with those cells. Idea is to fit 18kWh battery to Opel Ampera, only the cell modules and use everything else as is. This would include connecting battery cells in correct order to BMS and also temperature sensors. I will have to use original current sensor as well as original front plate with coolant hoses. and connectors.

I got some good data from post in https://www.diyelectriccar.com/threads/ ... ost-954522
I ran water through my batteries (2015 Volt, 12s module) at different temperatures and measured the resistance of the two sensors (one in each module). Resistance values are in thousands of ohms:

Temp °F__R1 kΩ__R2 kΩ
35_______27.1___30.9_
50_______18.5___18.9_
70_______12.5___12.4_
100______6.4____6____
115______4.6____4.2__
130______3.3____2.9__
Mechanically cells are similarily shaped and i think i can make some sheet metal clamping to fasten the cells in previous mountings.

In first place i need to connect the cells to BICMs and test BMS data output using SimpBMS. When everything is running OK i will move forward and gut our Ampera car and try to use it with BMS in the car.
Original Volt Gen1 BMS connectors are not good for Gen2 because they have plastic extrusions located in the wrong place for them to fit in the socket. However i found out Molex Minifit 5557-18R connectors have correct pin spacing and socket is correctly placed. P/N 39012180.
However connector does not lock in the socket even though it is quite a tight and deep fit. It is not possible to turn connectors incorrectly.

I am expecting Molex Minifit 5557 connectors with crimp pins soon.
Attachments
C4A Hybrid EV Battery Pack Cell Section 1 X2.PNG
3 temp.PNG
Temp sensor.PNG
arber333
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Re: Volt Gen2 battery using Volt Gen1 BMS

Post by arber333 »

Anybody knows which temp sensors are packed in Volt/Ampera battery modules? Are they 10K NTC thermistors perhaps?

At one point i will have to simulate them with correct resistor or just use another similar NTC thermistor. The latter would be preferable.
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Bratitude
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Re: Volt Gen2 battery using Volt Gen1 BMS

Post by Bratitude »

arber333 wrote: Sun Oct 17, 2021 3:59 pm Anybody knows which temp sensors are packed in Volt/Ampera battery modules?
Are they not the same as what’s in gen 1 packs?
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arber333
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Re: Volt Gen2 battery using Volt Gen1 BMS

Post by arber333 »

Bratitude wrote: Mon Oct 18, 2021 12:14 am Are they not the same as what’s in gen 1 packs?
Well yes, but i dont want to break perfectly good battery module to get to the sensor. Likewise heating up the coolant and reading the sensor seems rather large effort. I deemed it reasonable to search for data before i play with gen1 modules.
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