I wanted to put some things together about our eBikes, systems and batteries. This will be just about batteries.
Currently, almost every battery unit we sell uses LG Chem 18650 cells. We did for a time have Samsung 35e cells, but have not used those in some time. We are trying to get a better battery case, where the mount works well on our bikes, but also provides a USB port for running devices. Our first group of batteries we had with these specs worked well, but as the installer I wasnt happy with the mount. I had to modify it far too much for a simple easy installation.
Two trains of thought, one is to plug it in, and let it charge until the light on the charger unit goes to green. About 5 hours on full discharge. The theory is that the charger only puts out 54.6 volts, so it cant overcharge.
The other train of thought is to purchase a light timer, like what is used for Christmas lights. I have used one of the $9 versions from Home Depot where you pull pins for when the lights come on. Hook up the charger to it, and program it to charge for 2 hours, rest 1 hour, charge 2. This up down cycle puts less charging strain on the battery, and could potentially lengthen the total life of the battery.
The batteries are rated for 600 or more charge cycles. That is defined to be full discharge to full charged state. The batteries have a similar life cycle as a cell phone battery has. If you look up LG cell phone battery deterioration you can get an idea how most lithium ion based batteries perform.
Heat is a major factor in both the motor and the battery. We recommend during hot times of the year to charge the battery in a cool place. Since we are based in the Arizona desert, we see 120 degree and above garage temperatures, and know that is beyond the safe limits of the battery and charger.