|View single post by dan3192|
|Posted: Tue Jul 10th, 2018 01:20 am||
|I've been running HO scale BPRC engines for the last 5 years. A fellow modeler has asked me to power up a G scale engine for his backyard railroad. Early on I decided to use Li-ion cylindrical cells and have to decide which of two cell types to use.
For moderate use I can use Panasonic's 18650 x 3400mAh cells in a 6S1P arrangement which will provide about 75Wh of power with a max. recommended current draw of about 3.4A. Peak current draw is 6.8A. The six-pack measures approx. 6 x 4 x 7 cm. Cost is around US$39 with battery holders.
For heavier usage in terms of hours or load or grades, I can use Keeppower's 26650 x 5200mAh cells in the same arrangement which will provide about 115Wh. These cells have a max. constant current rating of 15A and a peak current rating of 30A. This six-pack measures around 8 x 6 x 7 cm. Cost is approx. US$65 with battery holders.
I've found that higher constant or peak current ratings in a battery have the advantage of starting and running better under load due to less voltage sag. The trade off is higher current capacity batteries usually have less total mAh capacity due to different chemistry.
For example, there is also available a Keeppower 26650 battery with a 4200mAh capacity, but with a constant and peak current rating of 30A and 50A respectively.
Depending on how my friend wants to run, we should be able to decide which way to go.
In any case, since I have been using both of these batteries for some time , I can highly recommend them in terms of stated ratings and quality of manufacture.
Hope this helps.
Last edited on Tue Jul 10th, 2018 01:29 am by dan3192