I'm about to buy 4 26650 batteries for a new torch and I was reading lifepo4 cells although less energy dense will last a lot longer (cycles) and will have as much storage capacity after 2 years as a lion battery as those tend to degrade. They also produce much higher currents. Any one have any experience using lifepo4 batteries in torches?
26650 cells, lion or lifepo4?
Gusper on 21/03/2015 - 17:16
Comments
Yeah I forgot about the lower voltage, I might need an extension tube to add another cell if I go lifepo4.
Not in an otherwise four-cell torch. You'll go way overvoltage.
If ultimate lumen-output is your goal, iron-phosphate cells aren't for you.
But doesn't the controller control the amperage, and it said 10 to 16v. I figured 13.2v should be fine.
LiFePO4 voltage is 3.2 - nominal - x5 = 16.
With the headroom you quote, you can risk it, if you're keen.
Not sure but I think one advantage of LiFePO4 is that you can charge them at very high amps (hi-amp solar panel reg?). Easily checked on google. Big advantage using them on an e-bike. I've now reconfigured the cells to 13ish volts and use normal car charger for past year to charge. Still working ok. Using for camping ect.
Have dabbled.
You will need a charger that has a specific LiFePO4 mode - I assume from your reading that you've gathered that.
Big con is the much lower cell capacity.
BIG pros are the safe chemistry - no risk of boom, and much lighter cell weight. In the context of 4 x 26650 cells, you will notice a very significant difference in the weight of your torch.
Also, while lumen output is reduced somewhat - courtesy of the lower voltage - emitters are far less likely to do a peak-voltage 'pop'.