Originally Posted by
Duster_360
The S is the number of cells wired in series (wiring in series, causes voltage to add) as opposed to wired in parallel.
So a 2S is two 3.7v lipo cells wired in series so the voltage is 3.7+3.7 = 7.4v.
The C is the discharge capacity and its a rating for comparing lipo performance (amp output). Discharge capacity is a function of teh capcity (mah) and the discharge rating. A 5000mah 40C lipo can discharge 200amps on a continuous basis (5000/1000 x 40 = 200). This C is also used to rate charging for lipo as in a '1C charge rate' - for the same 5000mah lipo a 1C charge is 5000/1000 = 5amps. A 2C charge is 10amps and so on.
All correct. But keep in mind, the discharge rate (25C, 40C, 30C etc.) is what the lipo CAN handle. NOT what it will put out.
So if you have a 5000mah 40C lipo it is capable of putting out 200 amps continuous as stated. But if your truck is only drawing 80 amps thats all it will do so basically its only using 40% of its potential. Say you have a 4000mah 25C in the same truck. It is capable of putting out 100 amps continuous. You are still only drawing 80 amps so either battery is more than adequate. You may notice a small performance increase with the 40C but IMO not enough to justify more than doubling the price in most cases.
As a rule of thumb, try to keep your vehicle demand at about 75% or less what your lipo is capable of doing CONTINUOUSLY. Don't get fooled by MaxAmps claims of "True 60C" garbage because that is their burst rate which can't be sustained for more than a few seconds.