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  1. #1
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    Cold+Battery+lights

    I commute and keep my bike on the porch overnight where temps can reach as low as -15 is it OK to keep my lights and battery (charged) out in those temps or should I bring them in at night? I am also concerned about the massive temp difference when turned on and if it will hurt anything.

    Thanks....Bob
    And I love beer!!

  2. #2
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    do not charge the battery below freezing !!
    you toast the battery and charger. it's a no-no.

    at -15C the battery has 30-35 less capacity,
    and it also shortens the life of the battery substantial, discharging it complete.
    general rule of thumb, at below freezing to -20C to -25C, double the capacity you need,
    protect the battery from cold , with a jacket, and don't discharge complete.
    double the capacity also, to reduce the current, and reduce the lithium-ion crystal buildup.
    working on some military batteries, good to below -52C.
    cheers, Rob
    http://mtbl.robs-x.com

  3. #3
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    Quote Originally Posted by rschultz101
    do not charge the battery below freezing !!
    you toast the battery and charger. it's a no-no.

    at -15C the battery has 30-35 less capacity,
    and it also shortens the life of the battery substantial, discharging it complete.
    general rule of thumb, at below freezing to -20C to -25C, double the capacity you need,
    protect the battery from cold , with a jacket, and don't discharge complete.
    double the capacity also, to reduce the current, and reduce the lithium-ion crystal buildup.
    working on some military batteries, good to below -52C.
    cheers, Rob
    http://mtbl.robs-x.com
    Thanks... So my best bet is to bring the battery in at night and keep it warm during the commute. I always charge inside but is it best to let the battery run down a ways before charging or can I charge every night. I am new to nice lights and just want to make the battery last.
    Thanks.......Bob
    And I love beer!!

  4. #4
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    asume li-ion battery, charge anytime above freezing,
    preferably, do not run down . new batteries do not exibit memory effect, like the old nicd, or sometimes nimh. more important , if the battery is not sealed, to protect it from salt and water, electronics do not like it.
    cheers, Rob
    http://mtbl.robs-x.com

  5. #5
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    Quote Originally Posted by bdundee
    Thanks... So my best bet is to bring the battery in at night and keep it warm during the commute. I always charge inside but is it best to let the battery run down a ways before charging or can I charge every night. I am new to nice lights and just want to make the battery last.
    Thanks.......Bob
    Yes.

    No battery likes to be frozen solid. They generate heat when you use them from the chemical reaction.

    Li-ion batteries have a finite number of charge cycles to them. Usually somewhere between 300 and 1000 depending on the quality of the battery (chemistry) and the quality of the charger.


    J.

  6. #6
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    Thanks guys for the help it's going to be nice to finally see on the way to work this morning (-8f)!

    Bob
    And I love beer!!

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