Tuesday, October 10, 2017

Charge a smartphone battery without the phone nor the charger

I shortly dipped my phone in sea water and the charging/battery control circuitry and micro USB plug got oxidized beyond repair (salt is really terrible). I could have saved it at the time if I had a chance to open it and carefully rinse the electronics with non-salted water immediately, but I miss my tools on holidays... While waiting for a replacement part to arrive, I had to recharge the battery the DIY way.

Recharge a smartphone battery with a super cheap lithium ion recharging module and pogo pins.
The short pieces of thick copper wires (in blue) are compulsory to present the retractable pins correctly
They are maintained in perfect contact with clamps on a soft silicon mat.

Shown above and below is a dirt cheap way to do the job.

You need 2 "pogo pins"
and a TP4056 Li-Ion
battery charger.
It uses a LiPo charger module based on a TP4056 (e.g. like this one at $1 on ebay, but you can get 5 at this price for less than $2!). Check the voltage of course, but both the battery and the module have electronic protections so you should be safe charging most of cellphone batteries.

I also use two retractable pogo pins (eg. $1.50 for 50pcs on ebay) soldered on two short, thick copper wires. The latter is important to position the pogo pins correctly in from of the battery terminals (do not mismatch them!)

By the way, I am using a silicon mat for all my solder job (and they are cheap: $4 for this 23x18cm mat). I tried various sizes and colors but I do recommend the white and small ones. This is even more useful than a self-healing cutting mat in my opinion, but mostly because I do not cut a lot of things.

Since it is both soft and sticky, it helps a lot holding the module and battery efficiently with a pair of clamps that can be found at the nearby hardware shop.

As a side note, we are living in interesting times... the specific board I need to replace on my phone, a Galaxy Note 3 from Samsung is only $3.27, shipping included from China. I would have to pay more just for one of the connectors, or ribbon cable!