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Lets say you have a 1500mah lipo battery and the same 1500mah in other types of batteries. What will be the difference in run time? . Any difference in the lipo batteries made for airplanes vs the ones made for cars or boats? There is so many diferen't batteries with a huge difference in price. I'm confused

i could be wrong but as far as the run times i think they should be close to the same between 1500 and 1500. (if i'm wrong can someone explain it to me). now the lipo would give you a hair more voltage comparing the 7.2v 6 cell ni-cd or ni-mh vs. a 7.4v 2 cell lipo.

as for which one to choose look at these questions.

will it be for bashing or racing. is racing you are limited to 2 cell 7.4v in a hard case.

do you have size restrictions. some of the airplane lipos i have seen are very long and skinny and wouldn't fin in a rc10.

if you want longer run times look into lipos with higher mah but remember some of the larger capacity ones get physically bigger too.

if racing also make a note that the lipos are lighter than the ni-cd and ni-mh packs so in some cases you may want to also add a little weight.

hopefully some of the others can chime in too.

lipo's also don't like being discharged higher/faster than they are rated, unlike nicd/nimh, which are a much tougher construction. Nicd and nimh will get hot when discharged too quickly, and usually, the cells with vent in extreme cases, making their capacity much less, but overall, the end case is simply some bad cells.

with a lipo, they are rated based on their 'C', which is basically, the charge 'C'apacity. They are typically charged at 1'C', so in your case of a 1500mAh battery, would be 1500mA(1.5amps) for a 1 hour charge cycle.

now, the trouble comes in that lipo's are rated for their discharge 'C' as well, which is why you see something like 15C or 25C.

simply put, discharging the cell beyond it's C rating will cause problems, including puffy cells, cell damage, and worst case, intense fire/flames.

it's best to stick with a car based battery, from a decent known brand, since the capacity and C ratings will be geared for the land use, as well as construction.

In my personal experience, although the battery ratings are similar, it just seems like the lipo's run longer. The maintenance free nature of the lipo makes electric r/c much more enjoyable and less expensive. I agree with what was stated above. Stick with a car based pack instead of a plane pack due to the C rating being higher with the car type. Use a good lipo charger, buy a reputable battery, don't overdischarge, and you shouldn't have any problems!

Some feel the need to go and buy the largest capacity cells they can, but try to match the pack for the type driving you do. If you want maximum runtime, then yes, get the large capacity. If you plan on racing where the races usually last 6 minutes, save yourself some dough and get a smaller capacity pack. Remember, if you get a 6000mah pack for bashing, 30 minutes runtime is great, but the limiting factor there will be motor temps. I run an Orion 3200 pack in my RC10B4 equipped with a 10.5 bl motor. It is enexpensive, light weight and gives me 15 minutes runtime. I have also found that the Orion cells need minimal balancing, if any at all. The hard case is a bonus as well.

Yea runtime is what I'm after as there is no racing aruond here. What determines the runtime the pack will give me, the MAH? Does the same apply to non lipo batteries?

yes, run-time is dictated by motor wind, capacity of the batteries, gearing, and losses.

assuming geared properly,
the higher the wind, the longer the battery will last
the higher the capacity(mAh), the longer the battery will last
the less loss you have, the longer the battery will last(wire losses, mechanical esc worse than electronic esc, etc)
the less friction you have, the longer the battery will last(light lube, ball bearings, etc).

everything adds up. the motor wind, gearing and battery capacity have the most effect however

illshou wrote:Yea runtime is what I'm after as there is no racing aruond here. What determines the runtime the pack will give me, the MAH? Does the same apply to non lipo batteries?

nimh batteries lose alot of energy as heat, lipos last longer for the same capacity because they don't get hot.