What’s the c on lipo batteries?

[DHarb]

What is the C on the lipo batteries for? I’ve heard you don’t wanna go to low but is there such a thing as to high? I have 2S lipos at 50c for my brushed senton mega. Any thoughts on different batteries? I burned up two motors already.

 

[vpr5793]

Think of "C" as the (dis)charge rating in terms of the capacity. 1C basically is the time it takes to charge/discharge the battery in one hour. For a 5000mAh battery, this is 5 amps.

So a 25C 5000mAh battery is rated for 25C discharge, which is 25x5000mAh = 125,000 mA. or 125A

 

[LibertyMKiii]

You want to go high and there is no such thing as a real C rating.
All the manufacturers lie about their C ratings.

If you saw two on the shelf and one says 25C and the other says 50c. You would go for the 50c thinking it is better....
No one regulates or verifies the numbers so companies are now putting 150c on batteries which isn't even possible.

At any rate it is still better to buy the highest C value battery you can afford.

 

[vpr5793]

You want to go high and there is no such thing as a real C rating.
All the manufacturers lie about their C ratings.

If you saw two on the shelf and one says 25C and the other says 50c. You would go for the 50c thinking it is better....
No one regulates or verifies the numbers so companies are now putting 150c on batteries which isn't even possible.

At any rate it is still better to buy the highest C value battery you can afford.

Everything ^ said is also true.

 

[Primarrma]

So the issue with the the c rating being too low is because the equipment is drawing more than the battery is capable of providing, so something has to give, for example I have batteries that became puffy when I ran them hard in my k8s with a Max 5 esc and 56113 motor combo, and these where batteries that should have been able to produce that kind of current.

The equipment will only draw what it needs, so having a rating above the limit of the esc is a good thing as it will only ever draw the maximum of the escs capability, if that is below the limit of the batteries acceptable amp draw then that's good. It will mean your battery will be OK for longer and the electronics will have good clean power without any brownouts being sent to it.

 

[vpr5793]

More "C" than needed also means less stress on the cells, which reduces heat. Heat is one of the primary ways that Lithium batteries' lifetime is reduced. So reducing heat will allow the battery to have a longer overall service life.

 

[DHarb]

So the issue with the the c rating being too low is because the equipment is drawing more than the battery is capable of providing, so something has to give, for example I have batteries that became puffy when I ran them hard in my k8s with a Max 5 esc and 56113 motor combo, and these where batteries that should have been able to produce that kind of current.

The equipment will only draw what it needs, so having a rating above the limit of the esc is a good thing as it will only ever draw the maximum of the escs capability, if that is below the limit of the batteries acceptable amp draw then that's good. It will mean your battery will be OK for longer and the electronics will have good clean power without any brownouts being sent to it.

So how do you exactly know how much “C” you’ll need? I picked up a blx now and been running it with my 2S at the moment but definitely want to step up to 3s. I am seeing that they are usually around 35c. Any thoughts on that or try to go higher??

 

[Primarrma]

The system(esc) will have a max current draw, most blx systems require at least 35c which blx did you get? 50c would be a better option though.

 

[DHarb]

The system(esc) will have a max current draw, most blx systems require at least 35c which blx did you get? 50c would be a better option though.

I got the senton blx. Thanks for the info it’s much appreciated!

 

[rotauq]

I am not saying too high of a C rating is a thing. But the battery max amp draw (capacity(A) * C-rating) is one of the safest bottlenecks you can have in a system. Most esc's (RTR for sure) have plenty of safety systems. But a (high geared) motor (in mud/grass) will pull all the amps it can get to reach it's max/rpm or saturation point , even if it burns itself because of it.

The battery gives, the motor takes. Especially @SCT racing-style driving, continues ampdraw can be near the esc/motor capability making it run hot and 'wear more' (definitely on brushed systems). It can be a better option to have the battery bottleneck the system 2s every 2 min than to have it run hot/ fall in protection mode every 3 min.

Brushed esc's were designed with NiMh batteries in mind, and those have a much lower C rating. Any decent capacity 2S battery will never be the bottleneck and put all the stress on the motor (and esc if it runs hot). If you wanna increase the lifespan of your motor(s), ease of the throttle from time to time, or drive with a smaller pinion.

 

[*420+3RC*]

Just info.....i run a 3s 5000mah 50c smart spektrum. Its great! Little pricey at 75$. But I run a BigRock. And without draining battery all way down I get 45+min hardcore bash time no heat issues

 

[Primarrma]

.