Off Grid Home Forums Technical Discussion Why not recycle li-ion batteries and use them for OTG systems? Re: Why not recycle li-ion batteries and use them for OTG systems?


Yes, the 18650 battery is similar to AA but slightly larger and higher voltage. AA is 14.4mm x 50.5mm and 1.5 vdc. The 18650 is 18.6mm x 65.2mm and 3.7vdc, and 2200 to 3400 milliamp/hrs. and average is greater than 1000 cycles of charge. The L16 is around 2,900 cycles of charge.

The closest you could come to a viable solar electric is hooking 7 of them + to – for 25.9vdc and 130 of these sets – to -, + to + for around 390 amp hours, and of a voltage that could be charged by a 24 volt charge controller and driving a 24vdc to 110 vac inverter. It would be equivalent to 4 6vdc L16S batteries with a total of 6 connections vs 3,640 connections.

Cost without the connective wiring is around $940 for the 4 L16s, and $910 plus shipping or so direct from China. Obviously, the connections would cost a lot more.

For a 12vdc nominal, the closest is 130 sets of 4 18650 batteries with 1,040 connections for 14.8vdc, which would drive a 12vdc to 110vac inverter. However the voltage is too high for most 12vdc charge controllers to be very effective. It would be close to equivalent of 2 L16s for $470+, while the 18650s would be $520 plus connections and shipping from China.

With the fact that they are less than 1/2 as good for cycles and so many connections, it is highly impractical, as treasuregift said, for any alternative energy system.