Battery capacity. What's nominal?

[ChILd_ReBoRn]

So, since I'm trying to built a rc vehicle on a budget, I decided to build my own battery. Not sure how "big" should it be. I've ordered the PCB, and I think 3000mAh should be enough (3S). I have 2 motors and 2 servos. The dozer is about 30cm big, 6 lbs max. Will it be able to have a 30 min play cycle? Or should I just try to cram in 3S2P battery? That would be massive 6000mAh, more expensive, bulky, PCB won't work for balancing and it would be heavy. Even charging would take a long time..

I'm inclined to 3000mAh, but open to suggestions.

Ty

[Lil Giants]

Buy two 3000mah

[ChILd_ReBoRn]

And swap them when one is depleted?
I have some 18650 cells lying about, I'll solder them in 3S configuration and use it for testing purposes. If they suffice, I'll order a dedicated LiPo pack(s).

[skeeter]

Originally Posted by ChILd_ReBoRn

And swap them when one is depleted?
I have some 18650 cells lying about, I'll solder them in 3S configuration and use it for testing purposes. If they suffice, I'll order a dedicated LiPo pack(s).

The 18650 batteries are not designed to handle the discharge rate(s) that may be put on them. For a test they should work one or two times.

As Joe said TWO 3000MAH batteries is good. That way you can have one on the charger while you're running the other.

[ChILd_ReBoRn]

ok.. something new learned. 3000mAh going on the shopping list

[nes999]

I sort of feel my like 10,000 Mah will be severe overkill when it arrives...

[Bo Wallen]

Originally Posted by nes999

I sort of feel my like 10,000 Mah will be severe overkill when it arrives...

Lol. Three times the runtime wouldn't. hurt Or?

[frizzen]

3000 mAh should be plenty.
Do you need 3s or would 2s voltage still get what you need?

[ChILd_ReBoRn]

Nah, I ordered 3S. 7,4V would be to slow

[skeeter]

10,000MAH batteries are AWESOME! I run it for the RC4WD 4200XL Excavator, as well as in the Faroe loader. I can run a half days work on ONE battery. Then I have to resort to the back up battery, a 6,800MAH battery to finish the remainder of the day....Well ALMOST the remainder of the day.

[Cooper]

You guys would be better to use two separate batteries and just plug them together (parallel) , when a is 3s2p. You have six cells. You never truly get a balanced charge (that's where potential problem occur with lipos) on all cells. Yes you have two batteries verses one but you also have the ability to maintain two separate batteries. And if you are "making " your own packs keep in mind they are not electrical storage devices but mini chemical reactors, store appropriately.

Just my .02$ , I rarely read directions and am always doing what I'm told not to but when potential injury, or fire results can happen better safe than sorry.

[ChILd_ReBoRn]

I agree with you about balancing problems with 3s2p. 10kmAh is a serious overkill and logistic problem for me, so it is out of the question..

[nes999]

Yeah mine is just 7.4v for so shouldnt be much of an issue balancing wise.

[tylor]

can lipo battery be used on this truck? such as 7.4 v lipo battery from some brand.

[skeeter]

Yes, 2S LiPo batteries can be used in the Tamiya trucks.