DIY Power bank from recycled vape batteries.

I've used 5 batteries from a rechargeable vape. Each battery has a 650mAh capacity, so the total is approx 3250mAh. It charges most modern phones to above 65% from 0%.

USB Charge Power Bank Module Circuit Board used: 134N3P
This is the board I purchased: https://www.ebay.co.uk/itm/264463774745
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==SAFETY==
A lot of people are asking about safety so I thought I would add this here.

The charge module, also known as BMS (Part 134N3P, above) will make sure that they are never overcharged (max voltage: 4.2v ±1%) and also never over discharged (max voltage: 2.9v ±1%). It also makes sure it does not discharge them too fast (Output current: 1A (max)) and also that they are not being charged too fast (Charging current: 1A (max), in my two builds, the max charge current is only 0.5A). To top this up, it also offers overvoltage protection, short circuit protection and overload protection on the output.

To reiterate, since the batteries are in parallel, you only need one BMS (Charge module) to protect the whole pack as there is nothing to balance. By definition, parallel cells will naturally balance since they are directly connected to each other.

*If you have a circuit that can be added to make this safer, please post the part in the comments.
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==BATTERIES==

IMPORTANT
Remember to charge all 5 batteries independently BEFORE you solder all of them together!
IMPORTANT

They all have to be charged independently so when they are soldered they are all "balanced". This way, each of the 5 batteries will discharge at the same rate and charge at the same rate. As best as they can. If you don't do this, things WILL go wrong!
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==TIPS==

Try to have them all within 0.1V of one another, before soldering

After soldering them in parallel, leave the batteries alone for 15 to 30mins so they can balance automatically, this will remove any discrepancy left
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==CHARGING YOUR BATTERIES==

The batteries I used all had mini charging circuits attached to them, so I just used that to charge them and then I removed it before soldering.

If your battery does not have this, you can just use the circuit for the whole power bank to charge one at a time, maybe use a set of alligator clips to make it easier, or just solder. [Last picture is an example of this!]
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Once everything was put together I used hot glue to make sure not nothing gets moved about.

For info, my one takes about 5 hrs to charge from dead as it charges at 0.5A.

Also, the little 45° notch on the lid is to make it easier to open it up again after it has been closed.

it's not the fastest but it sure works!