# Battery for bicopter

Hello!!

I am building a bicopter and right now i am using a lipo battery 11.1v and 2200mha. It seems to be too heavy and i was wonderi g if i can use a smaller one like a 1500mha or 1200mha???

I am using two brushless motors (hobbymate 2204) with two 18a ESCs

What do you think?

Thanks

I think you'd be better asking on a model aviation forum.

Units of battery capacity are "mAh", not "mha"

Sorry for the typo

rossi86m:
Hello!!

I am building a bicopter and right now i am using a lipo battery 11.1v and 2200mha. It seems to be too heavy and i was wonderi g if i can use a smaller one like a 1500mha or 1200mha???

I am using two brushless motors (hobbymate 2204) with two 18a ESCs

What do you think?

I think for a proper answer you really need to know how much current the motors are actually using. Do you have a wattmeter to measure the current?

If not then perhaps we can assume it’s less than 36A (2 x 18A). There are smaller batteries that can handle that much current. If you look for a 3S 1.1V 1500mAh with a C-rating of 30 or more that should be o.k. Even a 3S 1000mAh with C-rating 40 or more will probably work. The C-rating is important.

Of course there’s a trade off…the smaller the battery capacity the shorter the flight time you’ll have.

Steve

You have two issues to deal with, capacity and maximum amperage rating of the battery. C rating was mentioned above, and that is the relationship between the mah capacity of the battery, and the maximum sustained amperage it can deliver.

A 30C battery with 1200mah capacity would be capable of delivering 1.2 x 30=36 amps for 2 minutes (less the amount you need to leave in the battery to not have it drained fully).

I would start with figuring out your maximum current draw, and do the math for both how long the battery can last at that draw, and whether the amperage drawn is within the C rating of the battery.

I only find some lipo batteries can actually deliver at their C rating without sustaining damage. Some of the cheap ones can't, and become damaged quickly.