Test for and fix overvoltage conditions

ClemensElflein / OpenMower

Let's upgrade cheap off-the-shelf robotic mowers to modern, smart RTK GPS based lawn mowing robots!

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Test for and fix overvoltage conditions #95

Open ClemensElflein opened 3 months ago

ClemensElflein commented 3 months ago

when the mower is fully charged and the mowing motor breaks, the induced voltage spike might be too high.

we need to verify that this is happening
if it is happening, we need to protect against it

quelqundev commented 3 months ago

Hi ! I would recommend to never charge the battery at full charge to be able to absord current rejection. Is it possible to configure a max charge voltage ?

Furthermore i belive it is better to avoid little cycle charge at high % (i mean it "costs" more cycle charge to do 20%=>50% than 70%=>100%). Maybe adding a max charge at 80% would allow to improve the battery longevity ?

I'm trying to help, thanks for your great job guys !! 👍

ClemensElflein commented 3 months ago

you can set the max charge voltage to whatever you like, what do you mean it "costs" more to charge the last 30% than other 30%?

anyways the original issue is still relevant for people who decide to charge the battery to 100%

quelqundev commented 3 months ago

I recommend you to read this good article : https://accubattery.zendesk.com/hc/en-us/articles/210224725-Charging-research-and-methodology

The more important principle about Lithium battery is to stop charging before the "constant phase". Thus i consider it is to you to find a balance between charging at full capacith but "degrading" battery capacity faster...or charging at 80% but preserving battery capacity for longer time. 🔋

It's like a bonus that allow you to solve the hypothetic case of current rejection. 😎