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Does heat do more damage to a fully charged HV battery or depleted battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by JC91006, Jun 15, 2015.

  1. JC91006

    JC91006 Senior Member

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    Since summer is now here and the 100 degree heats are the norm, would you HV battery experts think the heat would do more harm on a fully charged battery or one that's been depleted?

    There are cars that I don't drive all the time and they are left baking in the sun. Should I store them full or depleted in the heat?
     
  2. bisco

    bisco cookie crumbler

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    fully charged. as you know, i am not an expert. and i maybe thinking about li-on.
     
  3. JC91006

    JC91006 Senior Member

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    I thought batteries expand with heat.....so I was thinking more on the depleted side. But I really don't know either
     
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  4. bisco

    bisco cookie crumbler

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    do you use window shades or anything?
     
  5. JC91006

    JC91006 Senior Member

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    yeah, the windshield shade, but that doesn't do anything when the temperature gets over 100 degrees
     
  6. bisco

    bisco cookie crumbler

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    that is hot. is it a dry heat? not that it matters to a battery.
     
  7. CR94

    CR94 Senior Member

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    somewhere roughly midway between is better than either extreme, I think. (I don't know exactly what degree of charge would be optimum, though). Note that the battery management programming in the car won't let you fully charge or fully discharge the battery, despite what the display may show.
     
  8. bisco

    bisco cookie crumbler

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    good point. i think we do know that arizona and texas batteries have a higher failure rate, don't we?
     
  9. andrewclaus

    andrewclaus Active Member

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    I think this might be a "how many angels can dance on the head of pin" kind of question. But I like it!
     
  10. alekska

    alekska Active Member

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    Fully charged battery is more damaged by high heat than empty one. This was discussed many times here.

    - Alex
     
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  11. JC91006

    JC91006 Senior Member

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    I'm glad somebody follows those threads......