I'd like to build a portable battery pack with which to use my laptop longer in the field. I've made a couple attempts with Chinese BMS boards that supposedly allow balanced charging and discharge/overcharge protection. However, the quality of these boards is very poor and they are always burning up or killing cells. I would love to to know if anyone has had success with a similar project .
>>26324 I've looked at these circuits on Banggood - I have a couple of electronics projects that I wanted to power using the common 16550 batteries for. I found some "kits" on there to basically build your own portable battery chargers/packs for phones, but I'm quite the beginner with this sort of stuff.
I've used a couple for Raspberry Pi projects, but those were essentially just a a step-up and a diode plugged in to a LiPo. I doubt I could make a proper, safe board for higher power stuff any better than the Chinese. Maybe the best bet is to cannibalise a USB power pack?
Also, they do already make laptop power banks. I don't ever want to dissuade someone from making something themselves, but I use a Poweroak K2 which is 50kmAh and does 100W. It's nice. It's also about a hundred quid, mind.
I wouldn't go to the effort, because an off-the-shelf power bank with 19v output will cost you about the same as the components.
If you don't trust Chinese BMS boards, I'd suggest using an iMAX B6 balance charger and an RC battery pack. The B6 is cheap but reliable and will charge 6s packs at up to 50W. You'd only need to solder a couple of pigtails on to a boost/buck converter, saving you the perilous task of soldering directly to the cells. If you need really long running times and don't care about weight, you could use a sealed lead acid battery.
