[Michael_Lambert]

Hey guys,

So i have been sourcing out parts i was going to build some packs. However i ran across a couple of sites who are selling packs for decent prices.

7 cell pack 8.4volt 5000mAh for $40USD.

Now of course i would have greater run time compared to the 3600mAh batteries i have now, i am wondering how does that effect charging? How long would a decent charger take to charge such a battery?

[Guest]

you want to go lipo, lighter, more run time and consistent voltage output,
any of todays competition chargers will charge 5000 nimh in 1 hour or less, same with lipo.

[Michael_Lambert]

Lipo? Is there much of a difference in cost? I understand that Lipo batteries really need to be cared for.

I have a horrible habbit of just pulling my truck out running it till the batery dies or i get bored and tossing it back into my garage, when i want t run it again toss the battery on teh charger untill i get tired of waiting and go run it again till pretty much it dies or again bored..

[big_bg]

Do not go with LIPO if you do not take care of them, lipo's will fail if they are drained below a certain level so if you run your truck till it dies the battery is already to low and will be furthur hurt by being put away for a long period of time. The 8.4v will give you a bit more speed over a lipo as well since a lipo cell is 3.7 volts, your electronics cannot handle a 3s lipo which means you relegated to a 7.4v 2 cell.Rui is correct with the large weight savings that lipos offer which will eliminate some of the speed gains realized from going with 8.4 v compared to 7.4v. From most of the people i've talked to who have switched to a brushless system with a 3cell lipo the truck is actually to fast.Lipos will require you to buy a charger capable of charging them, as well as i would get a lipo bag to store them in as they can be very dangerous if they light on fire (they burn very hot and the gas is extremely harmful) although if your in the market for a new charger then most middle of the road peak chargers will do 1-4 cell lipo.
With all batteries especially lipos i prefer to stay at one C so if it is a 5000mah pack i would charge at 5amps if it was a 3000mah pack i would charge at 3amps basically all batteries will take 1 hour to charge. I can't really comment on the quality of online batteries some manufacturers use good cells others use lower quality ones which won't last as long nor put out as much power

[Guest]

Lipo is less maintenance. Charge & go. You can get a lipo cutoff so that you don't over discharge it...like running till it dies for NiMh.

With NiMh you have to take more care of them, charge, discharge, balance, to keep them at their best. With lipo you can balance as you charge and there is no need to discharge before charging. As long as you follow the manufacturers charging instructions there will be no problems. You must also use a charger that charges lipo. Here is a good read for lipo info... http://www.fastcats.ca/battery_care.htm