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Eng Pro Guide Exam 1 (Batteries)

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TakiTaki

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Can someone please help me understand why increasing ambient temperature help increase the output capacity of the battery? What exactly do they mean by output capacity of battery?

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Flyer_PE

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Any battery is an electro-chemical device.  Increasing temperature tends to increase the energy released by the chemical reaction.  As an every-day example, it's why your car battery may work just fine on a 70 degree day and not be able to start the car when it's 30 outside.

 

Wow_PE!

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Can someone please help me understand why increasing ambient temperature help increase the output capacity of the battery? What exactly do they mean by output capacity of battery?

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Batteries perform better in higher temperatures except for extreme temperatures.  

Batteries have internal resistance (there are some good YouTube videos on this).  Imagine a 12 volt battery.  The load will not draw a full 12 volts because there is a small voltage drop due to this internal resistance.  12V = Vdrop + V_load.

In slightly warmer environments (not extreme), this resistance is less allowing for more output (volts provided to the load).

 

Wow_PE!

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Any battery is an electro-chemical device.  Increasing temperature tends to increase the energy released by the chemical reaction.  As an every-day example, it's why your car battery may work just fine on a 70 degree day and not be able to start the car when it's 30 outside.
I didn’t see your answer.  Sorry didn’t mean to give a competing explanation.

 

Flyer_PE

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I didn’t see your answer.  Sorry didn’t mean to give a competing explanation.
No worries.  I should have added that, for vented lead acid cells, you can find correction factors for temperature vs. battery capacity in IEEE Standard 485 (Sizing) and 450 (Maintenance and Testing).

 

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