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A comment on Ohm (YC S15) is a smarter, lighter car battery that works with your existing car. Parent comment

Re:Ohm (YC S15) is a smarter, lighter car battery that works... by eggoa on Wednesday August 12, 2015 @03:26PM (#10050048)
Will this work when its -30F?
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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by jngreenlee on Wednesday August 12, 2015 @03:32PM (#10050081)
http://www.mpoweruk.com/lithiumS.htm

Stricter regulations on shipping methods than for other cell chemistries. Degrades at high temperatures.

However, for Lithium Iron Phosphate LiFePO4: "Lithium phosphate cells are incombustible in the event of mishandling during charge or discharge, they are more stable under overcharge or short circuit conditions and they can withstand high temperatures without decomposing."

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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by conjecTech on Wednesday August 12, 2015 @04:07PM (#10050288)
The capacitors are fairly immune to temperature variation since they don't store energy using a chemical reaction, and we can also dynamically adjust the standing voltage of the caps to increase power in cold conditions.

We believe so, but don't want to say it until we can verify for sure. Our temp chamber unfortunately has trouble pushing anything south of -20F and it's a bit hard to find weather that cold in August.

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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by disposition2 on Wednesday August 12, 2015 @03:34PM (#10050090)
I would be interested in this and high temperatures as well, few things perform as expected here in AZ when it gets above 110F
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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by fn42 on Wednesday August 12, 2015 @03:48PM (#10050179)
Not exactly -30 but I know this guy had some success with off the shelf caps: https://www.youtube.com/watch?v=GUXM1XuLUIs

There's a few other vids on this topic if you search through the channel

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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by daniel-levin on Wednesday August 12, 2015 @03:52PM (#10050195)
>> Rated for -30°C to +50°C [1]

-22F ~ -30C

[1] http://www.getohm.com/

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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by chrisBob on Wednesday August 12, 2015 @04:01PM (#10050256)
Is that expected to be sufficient? Typical automotive electrical components are rated over -40C to 85 or 105C. I think the engine compartment is typically hotter than 50C when a car is running. This might be more suitable to a car that mounts the battery remotely: I have seen BMWs with the battery in the trunk.
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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by blueintegral on Wednesday August 12, 2015 @04:46PM (#10050506)
We're being conservative with the temperature rating for now. The components are rated better than that, but we're still running cycle tests in our temp chamber and waiting to get the system tested by an outside lab.
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Re:Ohm (YC S15) is a smarter, lighter car battery that works... by beloch on Wednesday August 12, 2015 @06:22PM (#10051128)
It's not sufficient in Canada. We regularly see temperatures below 30 C. Hopefully they can push it lower, because a battery that quits when it's cold out is pretty much worthless up here.
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