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The Prius 12 volt charging system.

Discussion in 'Gen 2 Prius Technical Discussion' started by Britprius, Mar 15, 2013.

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  1. srivenkat

    srivenkat Active Member

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    John,

    When you say "not expect the car to charge it", did you mean to say the battery would actually be damaged as a result of the high current recharge done by the Prius right after a deep-cyle event? Or simply that the battery won't be charged enough by the Prius and so it should be kept on a slow 4Amp charger overnight?

    The new Yuasa label still says the charge current should be limited to 4.2 Amps I believe. Whereas the new Exide Edge specs simply say "Fast Charging"-capable (75 minutes recharge at 25 Amps). Does this mean the Exide can charge up at higher currents whereas the Yuasa may not? IIRC the Optima isn't recommended to be charged at more than 10Amps? Not sure what SuperStart recommends.

    I am just trying to understand these from a layman-perspective to see if one battery might withstand the high current charges by Prius better than others.

    Thanks.
     
    #21 srivenkat, Mar 6, 2014
  2. Britprius

    Britprius Senior Member

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    The reason I recommend charging a fully discharged battery with a charger rather than the car is because of the high current the Prius will charge at.
    This is advice is mainly aimed at the OEM battery that as you correctly stated says charge rate 4.2 amps max. I suspect this is the highest rate it can be charged without gassing at to high a rate and venting, thus drying it out. Sealed batteries have a catalyst that convert the gasses back to water, but at high rates this can become overwhelmed and the gasses are vented.
    This I believe is the reason the OEM battery does not stand up to deep discharge well, because on being recharged on the car the charging system dries it out.
    The Exide as you state has a maximum charge rate 6x higher and should cope much better, but if the opportunity exists I would still prefer to use the correct charger that can be governed to below the safe charge limit.

    John (Britprius)
     
    #22 Britprius, Mar 6, 2014
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