I have a 50w all in one hobby charger, as well as a 300w capable one...
I am researching building a 12v 4s2p 50Ah LiFePO4 battery to use with a small 20lb thrust trolling motor. Max amp draw should be 15-20 amps, but I will be running it through a PWM so draw will usually be lower.. This is for a kayak build.
The BMS's on Amazon don't get very good reviews, and I am not sure about shipping delays for the Daly ones from aliexpress.
My idea would be to top balance the cells in parallel if the V is close; then build the pack. If I don't have a BMS by the time it's warm enough to go on the water, I would use the RC balance charger, add a JST 4S lead and a low-voltage lipo alarm to manually monitor the cells.
After a day on the water, plan is to:
Set the RC Charger to 4s LiFe at 15amps, set it on balance charge profile, and bring the charge back up on the battery with the balance leads connected to the charger.
Max voltage on the LiFe profile is 3.6V; nominal voltage is 3.3V - I don't think I can adjust these numbers further; but they should be right. I can take off the Timer and the max capacity so it won't stop until the battery is full.
The balance discharge on my 300w charger is 200mA/cell
I thinking this is a safe way that I can operate the Battery until I get a BMS? The balance charger should protect the battery while charging, the LiPo alarm would alert me if a cell goes too low. I can set it in 10th of a volt. I am thinking of setting it to 3.1(?)V
Build is contingent on finding LiFePO4's for a good price. If not, I will run some 4S Lipos as a stopgap....