I am building myself a laptop. I have now come to the problem of implementing a lithium battery for it.
It will have to power the SBC and the display I use.
Both require 5V;
the SBC comes with a 2.5A charger,
the LCD has a maximum power consumption of 15W, so 3A.
The charger for the SBC is propably a bit overkill, though I would like to have some room to connect USB devices that also need some power (thinking of harddrives with dual USB for power).
My question is what battery suits my case, and what circuitry I need to not ruin it and to be able to use it in a laptop-like fashion.
First off, I think some UPS-like board would be needed to quickly change between charging/discharging the battery. Do you know where I can get something like that? I searched a lot, but all I find are battery protection boards.
When buying a battery, these will most likely already be included – but can I rely on those when charging and discharging?
And lastly, how does some kind of "fuel gauge" fit in the picture?
Best Answer
I think I will go with a commercial OTS power bank. This will probably solve my problem the easy way - since those already take care of charging and protecting the cells. There are still criteria the pwoer bank will have to meet: It needs to be able to be charged and discharged at the same time (bypassing the cell in this situation), and have a high output current. There are power banks especially made for notebooks that meet those criteria. A 70Wh power bank should give me at least 3 hours of operation. I may need a buck converter, as my boards need 5V, but laptop bower banks often provide higher voltages, up to 19V.