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Discussion Starter #1
I know the car does not have a nice % remaining display, so Im thinking about developing a simple workaround if I can, but I have a question for the experts in the group. Is the SOC derived solely from the battery pack voltage? If thats the case then it should be simple to implement a workaround.
 

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whilst the voltage of the pack might be useful, and hopefully OVMS will find a way to get that from onboard canbus, it's not trivial to get the battery SOC from it, this curve explains:

 

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Discussion Starter #3
whilst the voltage of the pack might be useful, and hopefully OVMS will find a way to get that from onboard canbus, it's not trivial to get the battery SOC from it, this curve explains:
127444

Hmmm, I understand your point, but I think of it a bit differently. I use Li Ion cells and LiPo packs all the time and understand the max/min discharge curve, but a decent BMS will never let the battery pack into the extremes of this curve. Typical max charge will be 4.15 v and max discharge around 3.5v. So the actual usable range is more of a flat line if you consider the fact that as soon as the pack is under load (from fully charged to 4.15v) then it will almost immediately drop to something just below 4v. So I think the voltage should more or less give a good linear representation of the usable 100% to 0% range (between the red lines in the graph), its not 100% accurate, but certainly good enough to give the driver a damn good linear indication of SOC.
 

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The guys at OVMS have already found the SoC, but not via the OBD2 port. They have tapped into the car elsewhere.
The battery voltage when at 100% is somewhere around 448v from memory and when it is low is around 400v.
 

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This is the site they are using at the moment.
 
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