Battery is warm when not-in-use

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  • Updated 3 years ago
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I have a 7.5 Ah battery that came with my lawn mower.  Since it is for my mower, it hasn't been used for a few months. 

This weekend, I took it out of the shop drawer that I store it in, and notice that it was warm, specifically in the area around the "power" button.  Is this normal, or is this battery defective?

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Posted 3 years ago

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Blue Angel, Champion

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Official Response
Hi Dallas,

30 days after the last use or charge of the battery it will go into a self discharge mode where it depletes to 30% of its full capacity. This happens by using electric current in a resistor bank in the batteries' end cap.

Given the size of the 7.5 amp hour battery and the limited power dissipation through the cap, I imagine the self discharge process could take quite a while.

To answer your question, yes I believe what you're experiencing is normal and I have experienced it on two of my batteries as well. I made a suggestion to Ego to include this information in the manual but I haven't seen anything added yet.