Lipo questions

[Sammus]

Notice that a lipo's discharge rating is often given as a "C" value. That means it can discharge at that many times its capacity. So say you have a 6000mah = 6ah battery with a 25C rating, it can deliver 25*6 = 150A. If you have a 3000mah battery rated to 30C, it can deliver 30*3 = 90A. So basically the higher capcity batteries tend to have slightly lower C ratings, but because theyre much larger they deliver more current.

Secondly, didn't quite gather if you got this, so I'll tell you anyway :) one 4s 6000mah is not the same as two 2s 3000mah. The latter will either give you a 2s 6000mah (parallel) or a 4s 3000mah (series).

[Jbreddawg]

My understanding "way back from high school though lol " Is that when you run them in series you add the two so two 2s 3000's would equal one 4s 6000 ? And run in parrallel you would get 7.4 volts but 6000 mah ? is my memory not serving me correct ? It has been more then 20 years since school !!!

[Jbreddawg]

I forgot to put the link in my earlier post !!

http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA:IT&ih=016

[Hickoryhead]

Originally Posted by Jbreddawg

My understanding "way back from high school though lol " Is that when you run them in series you add the two so two 2s 3000's would equal one 4s 6000 ? And run in parrallel you would get 7.4 volts but 6000 mah ? is my memory not serving me correct ? It has been more then 20 years since school !!!

Your close. To run in series you add the cells together but not the mah's. To run in parallel you add the mah not the cells. Like Sammus stated:

two 2s2p 3000 mah packs---

2s2p 6000mah (parallel)
4s2p 3000mah (series)

And of course paraelle gives you double the run time and series gives you double the power output.

Be careful about the Lipo's you buy. They are very sensitive creatures. You get what you pay for. Just because the numbers on the packs look good does not mean they will perform good. I would not suggest to anyone about getting those batteries. There are to many factors when it comes to Lipo's. You don't need to buy the very best lipo but don't buy the cheapest you can find. Like I said you get what you pay for with Lipo's. That battery might be fine on a Helo but in a truck that is bashing and crashing they may not stand up to a beating or the cells might not put out the amps your looking for. Just my 2 cents though.

[Sammus]

Originally Posted by Hickoryhead

And of course paraelle gives you double the run time and series gives you double the power output.

Close, theoretically series gives you double voltage with the same potential current draw, parallel gives you the same voltage with twice the potential current draw - so the power is really the same, just in different forms :)

But for what it's worth, higher voltage is generally more efficient than high current, so it is better :P just being my pedantic self...

[Jbreddawg]

I really appreiate the great advice ! I was just using those as an example, i have enough money invested why cheap out now !! i do plan on getting good batts, i used to race along time ago and the quality batts made hugh differences !! I was just wondering if I could go with less mah but as i see now that will also hurt the output capability . thanks again for the teachings !! Jerry
p.s. my gorillamax G2R chassis and rc-monster motor mount showed up today !! And I purchased "dont tell the girlfriend" another roller to continue on with my own custom chassis build !!