I have a few relatively inexpensive hand-crank flashlight/radios. I keep them in my cars. I don't know the type of battery. Anyway, the instructions were to crank them periodically, even if not using. (I assume that means the battery is damaged if fully drained.) Unfortunately, I failed to follow the instructions after the novelty of them wore off. Now, the batteries are basically dead. Next ones I get, I will set a reminder in my phone to crank them periodically.
By the way, I think of these as a backup to a conventional flashlight, not as my first option. Also, they're bulky to carry. So, they are devices that reside strictly in my home or car.
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If you're reading this, it's too late.