Hey guys I am building my own raspberry pi portable for emulation and need help with power supply.
I have pic related as my PSU and it gives me approx 2 hours of run time. I want to increase the capacity of the battery so I am buying another one and am going to strip the second battery from the charging circuit and hook it up in parallel with the first battery.
My question is, is it safe to do so and would it work? Will there be any issues with the charging circuit or the way its going to function?
it might work, but cells have to be balanced to charge correctly. You probably want a 2-3 cell balanced pack. There are also cheapo chinese 10Ah supplies for cheap, which are also a good deal.
see that 18650 (the battery there)? they store a lot of energy but that means that while you can't say drop a battery and it will combust, overcharging (causing a breakdown of the lion barrier) is a real risk.
If two cells aren't balanced, one could say get 2 A while the other got .1 A, and if the max charge of that cell was 1.5 A, then you'd have a problem.
Honestly lion battery packs are so cheap you can get a good one from amazon for really cheap rather than building one yourself because of the economies of scale.
I bought one of these when it was on sale. powers the pi nicely for a few hours, haven't tried any tests to see what it can really handle