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Not charging ,, due to car was leaft too long without charging , sat for about yr

edited November -1 in Roadster
because HV Bat. is at or almost 0 ( zero ) V's car will not charge off a AC charger.. I held when this happen one needs to charge it with DC Voltage at very current..i guessing it be in mA of charge current ?? is there any problem by doing this ?? do want to take to tesla shop in south bay. have charged other Li-ion Bat. this way ..Have High Voltage , low current power supply , less 2.5 amp and can limit current down to less then 250 mA ( 1/4 amp ) or less if need be ..I know it may take several day at this low current to get battery up to the minium charging voltage , which think is around 2.5 V per cell ,,, 247 Volt for total pack voltage.. w
well BMS allow me to do this with doing any thing ??? do need to over ride some in BMS ??? does tasla have a shop maintance maunual for roadster ??


  • The battery is undoubtedly what they refer to as "Bricked". It probably can't be revived. Time to upgrade it to a Roadster 70 with the new 70 KWhr battery pack.
    I don't recommend you try to fix it yourself. You're likely to burn your house down.
  • edited October 2018
    you very likely just made yourself a very expensive paperweight. As Earl and Nagin said upgrading to a R80 battery if still available is your best bet.
  • edited December 2018
    You need to bypass the BMS board to do this. I have replacement BMS cards that slot into the BMS boards location to do exactly that, you can monitor at brick level and see if they accept a charge. if you charge them to the minimal brick voltage your charger will do the rest, probably best using the 110V charger to take it the rest of the way.
  • edited December 2018
    el brickaroo

    re kWh to horsepower.... thats applesto kumquats

    kWh is total energy (1kW of power for 1 hour).

    the valid conversion is kW to HP.
  • edited December 2018
    by el brickaroo i mean.... you destroyed the battery most likely.
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