I've fiddled, fiddled, built and tried several battery backup solutions for the Pi. Everything is somehow broken. This one works. No reboots when reconnecting power. Nothing weakens or heats up. I have not extensively tested its ability to maintain battery balance (2s). I2c and some SMBUS python will give you some real time information about power, -+ amps and TOTAL voltage and % SOC. . So yes, it's a bit pricey, but I immediately bought another one. Now you need to disconnect your Pi from 8.4V. I think 12v is probably fine too. Otherwise there is nothing to complain about. My Pi also powers a small 7 inch display, which hasn't been a problem yet. I liked three items that I bought from Waveshare. You always seem thoughtful and have the most important information to make things work. Oh! A note. I didn't like the brass posts. They worked, but they were weird, small and thinner. Unlike the stands that came with my displays.
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