I came across this today on ebay https://www.ebay.com...C4XsiiM5jKjHtDw
I have been wanting to get a power pack to run a small star tracker that fits in a back pack and this seems to fit the bill.
What I like so far: Its small, has a big velcro strap, and the USER has control over each battery in the container.
This means if a battery becomes unbalanced I can easily figure out the culprit with a voltmeter and replace it.
I think for such low draw devices such as a skytracker the springs would work fine, instead of the typical spot welded connections you see in bigger configurations.
What Im wondering now is if I can change out these lithium ions for Lifepo4 sized 18650's? It seems that the Lions are 3.7v where the Lifepo4 are typically 3.2-3.3v
so Im not sure if this would upset the BMS if I tried to change them out and charge them.