I did some searching around and found this older thread: https://forum.arduino.cc/index.php?topic=417890.0 This is similar to my question but I don't think the OP explained it well. I want to essentially have a charger where I can define the charging limit. The point being that it is bad for your …

Why would you want to walk out of the house in the morning with a phone charged to less than 100%?

wvmarle: Citation needed. I figured this would be common knowledge around here but there is plenty of information on the subject if you'd like to read it. https://www.sciencealert.com/here-is-the-best-way-to-charge-your-phone [image] Charge your lithium-ion battery devices for maximum …

I miss numbers in those articles on how much the damage really is. How much does it affect capacity or overall lifetime, really? The problem doesn't seem to be too great. I'd rather have my phone at 100% when I leave home than at 80% or so. Unless I carry a separate battery I normally have no chanc…

You realise that the smarts for the charger are inside the phone? What makes you think you know more about battery chemistry and safety than the phone manufacturer?

What makes you think you know more about battery chemistry and safety than the phone manufacturer? The OP actually believes what he/she finds in selected sites on the web. You can rely, for example, on articles found on " https://www.popsci.com/ " because they are contributed only by the top exper…

If you can ask the phone at what charge level it is (install an app, connect over Bluetooth or WiFi), you can have an Arduino switch on or off the charger externally.

I can't find where the OP asked if you agreed that this is a good idea or not. seems to me research into android ios, and programing for android ios is required, the arduino side will be easy once you can give the arduino values for current phone charge%. i don't know anythin about android ios, but …

Not going to stop OP from shooting themselves in the foot (well, as long as I can be quite confident it's not in a way that might actually get them killed). That doesn't mean I'm going to take claims on how those batteries work and should be treated at face value. As said, the biggest hole is that …

jremington: The OP actually believes what he/she finds in selected sites on the web. You can rely, for example, on articles found on " https://www.popsci.com/ " because they are contributed only by the top experts in the field :wink: sigh I had hopes this forum wouldn't be full of anonymous douch…

Intelligent phone charger with user defined cut-off

Projects General Guidance

wvmarle May 3, 2018, 8:31am 2

bluesk1d:
The point being that it is bad for your phone battery to be charged to 100% and even worse to be kept there (like overnight charging). In general, it is best to charge them to ~80-85%.

Citation needed.

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Intelligent phone charger with user defined cut-off

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