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Has anyone tried replacing the 12 volt battery with a LiFePO4 12.8 V battery?

Discussion in 'Gen 4 Prius Technical Discussion' started by GoodOldBob, Dec 1, 2023.

  1. GoodOldBob

    GoodOldBob Junior Member

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    I am interested in substituting a 50 or 100 AH 12.8 Volt LiFePO4 (LFP) to replace the Lead Acid battery. Mainly for the increased storage capacity and increased cycle life. Has anyone tried it yet? Did it work OK? Please let me know if you have done it.

    --GoodOldBob
     
  2. sylvaing

    sylvaing Active Member

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    Does that battery has its own heater to allow it to charge below freezing? Charging a frozen Lithium battery will damage it.
     
  3. GoodOldBob

    GoodOldBob Junior Member

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    Most quality LFP battery management systems include a low temperature cutout that blocks charging when too cold. Remember that the engine bay of the Prius doesn't stay below freezing for very long after the engine kicks in.
     
  4. bisco

    bisco cookie crumbler

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    Pretty sure this has been done multiple times, search google with Prius chat
     
  5. sylvaing

    sylvaing Active Member

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    Oh, right. The engine in the standard Prius is used quite often. I guess that could be different in a Prime.
     
  6. Doug McC

    Doug McC Active Member

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    You may want to investigate the charging requirements for each of the batteries. The charging algorithms for a lithium battery are significantly different than those of a lead acid battery. A starting point might be The Battery University (yep, it actually exists). Or, you could just rely on the opinions of folks who don’t even know there are significant differences between the two (like PC egineers (misspelling intentional) ;)
     
  7. Me_

    Me_ Junior Member

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    That question has been answered. Do a google search.

    In short due to a difference in the resistance between a standard 12v car battery and a lithium-ferric 12 v battery, you will burn the alternator; seriously burn it..
     
  8. sylvaing

    sylvaing Active Member

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    Good thing the Prius doesn't have an alternator then ;)
     
    Doug McC, ColoradoBoo and GoodOldBob like this.