Request for hardware startup: a battery charge level indicator part under $5 (for both rechargeable sand non). and I had a brief slack discussion (see screenshots) on why this is a hard problem that’s important and useful to solve. Any bright ideas?
Conversation
I don’t mean stand-alone. I mean one that can be easily integrated into devices that might have unpredictable batteries inserted.
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One solution is a simple voltmeter since most batteries demonstrate a decrease in potential (voltage) as they die. Many inexpensive battery testers are voltmeters of appropriate range with the units erased and a red/yellow/green bar placed instead:
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Most rechargable batteries for cordless power tools have this as a standard feature now.
They're on three of the batteries that i bought in the last two years.



