Long story short my charger doesn't work anymore so I thought I cut it up, solder it to a USB-A connector and use a normal phone charger to charge it.
Now I'm pretty sure the positive is on the inside and negative on the outside and that I have soldered it correctly, however to be completely...
sorry, beein trying to find this file that's been right in front of me for a month now, only to find broken links, and google to prove that it's completely worthless.