My Holux GR-213 GPS unit sat on my dashboard, in the Florida heat, without a sunshade for a couple of days, plugged in so the battery was charging.
Well, this was bad for the battery, and it swelled up, losing over half of its capacity as well.
I had a cell phone that a friend gave me so that I could use the defunct AT&T SIM card to unlock my wife's SMT5600, which had a battery. I got the idea to check to see if the batteries had compatible contacts. They did.
The cell phone's battery was larger in capacity, and I had to kind of jam it in a little, but it worked. I strapped it down with some rubber bands for awhile, until I found just the right piece of plastic blister pack that came with a water filter that I bought for my refrigerator. You can see the channels built-into the plastic, to keep it from flexing, lined up with the red arrows. I have already cut out the desired piece on the left, as shown.
I cut off a bit of that, with a channel it it just the right size, the same size as the battery, poked a couple holes in it, and screwed it into place. It works perfectly.
Note: I do not recommend that anybody else do this. It is potentially unsafe. Only I get to do stuff like this. Now go back to your desk job .
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