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Topic: MCP73871 damaging batteries  (Read 5444 times) previous topic - next topic

MarkT

A typical solar cell will have an open circuit voltage (voltage when no current is being drawn) about 50% higher than its nominal voltage. So if you have a "5V" panel it will be capable of reaching ~7.5V.
The "nominal" voltage of a PV panel is the open-circuit voltage with 1kW/square metre illumination.

The usable voltage of a PV panel is about 2/3rd of the nominal voltage.

So yes the over-voltage of the chip will be happening since it needs about 5V to operate and 6V max, whereas a PV panel usable to produce 5V at load will be more like 9V unloaded.

This charging chip is designed to work from USB, not a solar cell.  Other chips will perform that function, there are lots of specialist chips for all sorts of configurations of lithium cell charging/protection.
[ I DO NOT respond to personal messages, I WILL delete them unread, use the forum please ]

wvmarle

...
It always helps reading all comments as you'd have noticed you're replying to a necrothread... from well over 4 years ago.
Quality of answers is related to the quality of questions. Good questions will get good answers. Useless answers are a sign of a poor question.

pete_l

LOL yet another first poster adding a comment to a necrothread. How do they even find this old stuff?!
It doesn't matter how old the thread is, the information supplied is still useful and relevant.
As to how do people find this? It is the first search result on Google for MCP73871 and arduino

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