Suggestions for making the safest Smartphone charger from a 6S Li ion battery

[MikeLemon]

Hello,

So I've a beefy 6S battery I want to turn into a portable power station that will include phone chargers but I'm concerned that simply hooking it up to a step down power supply at 5V and connect it straight to an output usb port is not the right way to do it as the step down component may fail/ provide too much current to the charged device and simply destroy it.

I imagine that sort of circuit that includes over voltage and current protection for the output device to prevent catastrophic failure.

Any suggestions?

Thanks in advance.

[ilukester]

Not exactly sure how you want to go about something like this, however my first thought was using a powertool adapter. Kobalt 24v batteries are 6s and they make a dual USB output with 3.4A max. It does seem to have some protection circuitry. I can tear my open and take some pictures if you like.
https://www.lowes.com/pd/Kobalt-24-Volt-Max-Power-Tool-Battery-Charger/1000259305