Quick Lipo Battery question
 

Which is better or more efficient a 4s lipo or a 5s lipo? Also whats better between batterys like a 4s 40c battery or 5s 25c battery. I guess whats better the higher C rating or the higher cell count.
thanks for the help.

higher c rating is better. cell count is only voltage and nothing more.

hyp7, you need a little battery 101 :-)

"C" rating relates to the batteries current producing ability.
Current being a measure of amps. You didn't post the mah (milli amp hours) of the two examples. The mah is the number you multiply by the C rating to find the amps the battery is rated for.

For example lets say you were looking at a 4S 40C 5000mah battery versus a 5S 20C 5000mah battery. Which one handles more amps?

40C x 5 amp hours (drop the milli) = 200 amps at 4S
20C x 5 amp hours ... = 100 amps at 5S

So, what about watts? (that's the electrical equivalent to horsepower 745w = 1 hp) watts are calculated amps times volts.

Back to our example:
200 amps at 4S (14.8v) = 2960 watts OR 3.97 horsepower
100 amps at 5S (18.5v) = 1850 watts OR 2.48 horsepower

So clearly a 4S lipo at 40C will out perform a 5S lipo at 20C.

That's a 101, you can take it farther into watt-hours and internal resistance, but that's beyond the scope of your question :-)

Welcome to RC Monster by the way ;-)

Well, you have a loaded question.

If you run the exact same setup (motor, esc, gearing tires size) on 4s and on 5s, the 5s setup will draw more amps and go faster, but will likely make more heat, and have similar runtimes, or possibly less. If you have a setup that can be run on 4 and 5s (not exceeding the "sweet spot" of the motor) and you regear so that you have the same top speed with either 4s or 5s, the 5s setup will be more effecient.

A 4s 40c lipo will be capable of more output than the 5s 25c. Depending on your setup, gearing, motor, etc you may be able to run the 5s 25c lipo within its limits and thus it would provide a more effecient solution.

There is a big difference between 4s setups and 5s setups in heavier vehicles. 4s is marginal, even with the gangsta never lipos that are out. Going with a slightly lower kv motor and 5s lipo in a heavier vehicle stresses the components less and will lower amp draw and thus heat.

Any help?

Thanks for the responces that helps out alot.