Not specific to rechargeables, but had to put it someplace.
slmjim
Ah yes, I still remember the times when people could do a simple division without the help of a dedicated website.
(This rarely works for flashlights btw, at most a simple approximation.)
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There’s a Dutch expression for it: “Gemak dient de Mens” or “Why do Things the hard Way”.
I don’t know if “Bequemlichkeit dient den Menschen” is a legit expression.
The “hard way” being actually bothering to go to that website instead of just calculating it (by the help of a normal calculator, sure if needed).
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Cool
I wish there also was a battery charging time calculator.
Can’t be easily calculated because for example for li-ion cells, the constant voltage phase duration varies depending on the cells and initial charging current.
For Nimh cells end of charge detection can vary a lot between chargers and cells.
Self-confessed user of these online calculators here…
I was diagnosed as dyslexic as a child but have no problems with reading/spelling, I suspect what I actually have is something like Dyscalculia; It’s frustrating to explain as most people can’t empathise.
I’ll often use these calculators as a sense check then, once I grasp the concept, I’m more confident using excel or a calculator.
Well, how accurate do you need? If it’s a very rough estimate, and you’re charging from 2.8-3V (flat), the linked calculator is “okay”, if it were me, I’d add 10% to the cell capacity rating to account for the energy losses and the reduction of the current in the CV phase, you’ll perhaps not have a fully charged 4.2V cell (especially if you’ve old/high resistance cells) but it’ll be pretty close, in my experience.
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Hit it with stated capacity, power draw, then subtract 15% for good measure, lol.
I just straight up do runtime tests, much easier, although more time consuming.
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Sorry for misleading. I was sarcastic.
I agree that precise charging time calculation depends on many factors. But this applies to discharging as well. And since the linked site suggests to use simple formula for draint time calculation T=C/P same simple approach can be used for charging time calculation. But then it turns out that charging and discharging calculators do the same job and thus there is no need for a specialized calculator which does just a single arithmetic operation.
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