IP5358 mobile power supply 22.5W makes use of idle batteries

I picked up a 3*3 lithium battery and thought about how to use it, but there was nothing to do except make it a power bank. The current mainstream chip selection is IP5358. After reading the recommended circuit design, it is simpler than 5328. Much easier.

Since I couldn't find a suitable casing, I could only disassemble the casing, but it was glued together, so I had to destroy it by force. The single section was fixed, and I spent two yuan to buy 10 3p 18650 battery holders to form a 3*3 battery holder

Be careful of short circuits. The entire battery casing is the negative pole, and it is easy to short circuit around the positive pole. Be careful when disassembling. If you are not as lucky as me to pick up a battery pack that has not exploded, you should just buy the finished battery online. After the insulation sheet is put on the heat shrink tube, the lithium battery looks like it again, a bit like it.

The appropriate size of the PCB board was calculated based on the Pythagorean theorem, and four copper pillars were added to prevent metal objects from falling off the front and causing a short circuit. It can be turned over and used as a cover.

After all welding is done, the board will look beautiful after being washed with water. The board is as follows, verified.

The first use requires charging and activation, just plug it in and it will work. The 5358 chip design circuit is relatively simple. If you want to design it yourself, you can also optimize the circuit and put it on the power bank.

It is best to spot weld the periphery of the lithium battery with a spot welder. If not, you can also weld with old iron. It is easier to weld with a knife to grind the surface a little. After the welding is completed, apply insulating cushioning tape (actually tested, it is of no use. If you drop it, It broke after just a moment. Try not to drop this power bank because repairing it is super troublesome)

Start charging, and the test high voltage indicator light lights up to indicate that it is charging above 5V, and the output will also light up, usually 9V.

It’s done, it feels pretty good haha, all USB tests passed, go pick up a free lithium battery pack and try it!