[BrunoEV]

I'm trying to find a solution for charging 24 V Tesla batteries without adapting the settings for the lead acid batteries in my charger, becaus I want to charge those as well. This would result in a far too high charging voltage of 29 Volts. By adding a electronic relay in the charging circuit that is triggered by the BMS I want to create a Pulse Width Modulation charge process. When the battery is indeed reacting as a big slow capacitor I expect that this way of charging will not harm the battery.
Is this analysis correct?
Details: 2 Tesla S batteries, approx 10 kWh. maximum charge current 80 Amps, but this value can be lowered. Used in off-grid residential system
Your comments will be very much appreciated.

 

[BrunoEV]

Thanks a lot guys for all the useful advice and suggestions. I am aware that when anything goes wrong this will end ia a fire, so there must be an extra safety system based on another principle like the one suggested by Arklan.
Testing PWM on a simple 24V pack is also quite interesting, as well as looking at a stepdown converter.
All in all, plenty to think about!

 

[BrunoEV]

After considering all the options I opted for the safe but more expensive solution by choosing a 230 VAC charger dedicated for charging and protecting the Tesla batteries. The charger is linked to the BMS to keep the batteries healthy and safe.