Thread Tools
Sep 18, 2019, 05:03 AM
Registered User
Thread OP
Discussion

lipo battery shopping.


so im shopping for lipo batteries and i came across the C rating. do i need 30c or 50c? like im legit confused now. i fly my maule and i have a mini apprentice. and planning to get a e flite valiant. i know for a fact my maule take 40amps. so what do i need to get?
Sign up now
to remove ads between posts
Sep 18, 2019, 07:07 AM
aka: A.Roger Wilfong
gnofliwr's Avatar
First you have to take C rating with a grain of salt. Unlike mAh, which is pretty standard, C ratings seem to be different between brands. That said...

Everything else being equal, I always buy the highest C rating I can afford.

Higher C ratings mean lower internal resistance. Which means less voltage loss inside the battery and less heat generated. Less heat means longer life. Also, the lower voltage drop under load means better performance - since the voltage stays up, you get more power from the system.

Just don't expect that you're going to run at the full C rating for the flight. At 30C you'll get 2 minutes; at 60C, 1 minute.

- Roger
Sep 18, 2019, 08:47 AM
Registered User
Thread OP
Quote:
Originally Posted by gnofliwr
First you have to take C rating with a grain of salt. Unlike mAh, which is pretty standard, C ratings seem to be different between brands. That said...

Everything else being equal, I always buy the highest C rating I can afford.

Higher C ratings mean lower internal resistance. Which means less voltage loss inside the battery and less heat generated. Less heat means longer life. Also, the lower voltage drop under load means better performance - since the voltage stays up, you get more power from the system.

Just don't expect that you're going to run at the full C rating for the flight. At 30C you'll get 2 minutes; at 60C, 1 minute.

- Roger

my biggest battery is 100c and my smallest is like 30c. and i have smaller than that too. so should i go with higher c and low mah? i cant afford both high lmao
Sep 18, 2019, 09:32 AM
WJH
WJH
B747-400 First Officer
WJH's Avatar
With telemetry of current and voltage, it is easy to quantify the difference in C ratings. As others have said, higher C ratings offer less voltage drop when you increase the current.
With all of this said, I find that buying name brand batteries for the more expensive 4S and 6S large capacity batteries to be in your long term best interests.
I payed around 75$ from Banggood for 3 4S 5500 Zop Power batteries. All of them had mismatched cells, and all of them went bad sitting on my bench with a 50% storage charge on them. Luckily my Hexacopter has FrSky telemetry with individual cell monitoring, and under a load, in all the packs, one cell had significant voltage drop.
I now happily pay 75$ for just one battery if it is 4S or 6S, 5000 mah or more.
For 3S 2200 and smaller, feel free to buy cheap or expensive, high or low C ratings, and experiment with different brands. They are cheap enough to play with.
Sep 18, 2019, 10:04 AM
Registered User
Thread OP
Quote:
Originally Posted by WJH
With telemetry of current and voltage, it is easy to quantify the difference in C ratings. As others have said, higher C ratings offer less voltage drop when you increase the current.
With all of this said, I find that buying name brand batteries for the more expensive 4S and 6S large capacity batteries to be in your long term best interests.
I payed around 75$ from Banggood for 3 4S 5500 Zop Power batteries. All of them had mismatched cells, and all of them went bad sitting on my bench with a 50% storage charge on them. Luckily my Hexacopter has FrSky telemetry with individual cell monitoring, and under a load, in all the packs, one cell had significant voltage drop.
I now happily pay 75$ for just one battery if it is 4S or 6S, 5000 mah or more.
For 3S 2200 and smaller, feel free to buy cheap or expensive, high or low C ratings, and experiment with different brands. They are cheap enough to play with.
Excuse my ignorance but im confused? can i go with 30 c? i get what u saying dont go cheap on batteries which im not trying to do. i was gonna go with 2 of those https://www.horizonhobby.com/3200mah...3-eflb32003s30 and 2 of those https://www.horizonhobby.com/3200mah...3-eflb32004s30
Sep 18, 2019, 12:51 PM
FA34HM3YC7
Rhea's Avatar
I'll throw another thing in here, not to just confuse the issue but it may be worth knowing now.
I would recommend anything but E-flite batteries. There are a lot of others that will work well at a lower cost.

Just look for a battery that advertises a reasonably high C rate that is in a weight range and physical size that will work for your plane.
Sep 18, 2019, 03:20 PM
WJH
WJH
B747-400 First Officer
WJH's Avatar
Technically, this is what a C rating means. If you have a 5,000 MAH pack, and it is 30C, you theoretically could draw 5*30 amps. (Reality is that you could melt the connectors and or destroy the wires at that current draw)
Another thing, people will tell you that you can charge at 1c or 2c, etc. 1c for a 5000MAH pack would be 5 amps. 1c for a 3200MAH pack would be 3.2 amps.
I always charge at 1C, and I always leave my packs stored at 50%, which is about 3.85v per cell?
I also always land at 50% charge left, unless it is one of my ducted fans.
Sep 18, 2019, 04:58 PM
Registered User
FlyBigElectric's Avatar
I always charge at 1C, and I always leave my packs stored at 50%, which is about 3.85v per cell?
I also always land at 50% charge left, unless it is one of my ducted fans.

Great advice and I do the same. I get a lot of grief for being so "anal" about my batteries but I am also not spending a lot of money replacing them.
Sep 18, 2019, 06:16 PM
Registered User
stemo99's Avatar
Try Value Hobby for high quality and much lower prices. I’ve had nothing but success with them.
http://www.valuehobby.com/power-syst...-lipo.html?p=4
Sep 18, 2019, 08:34 PM
homo ludens modellisticus
Ron van Sommeren's Avatar
Quote:
Originally Posted by from video below
"... a lot of the time, C stands for crap ...

Have you ever wondered how a 100C battery gets away with an XT60 connector that is only rated for 60A? If you use lipo batteries in your RC planes, helis or drones then you need to watch this video and learn why the C rating of your batteries might not be what you think it is. There's also some other lipo info in this video that hopefully everyone will find interesting and of some value.
Lipo C ratings - fact, fakery and fire (23 min 37 sec)
Sep 18, 2019, 08:36 PM
homo ludens modellisticus
Ron van Sommeren's Avatar
About the marketing 'optimism', the nonsense and the blatant C-rating and capacity lies.
Active thread with with uniforum tests.
Battery Load Test Comparisons - RCG
&
www.liporatings.com

Virendelijke groeten Ron
• Without a watt-meter you are in the dark ... until something starts to glow •
e-flight calculatorswatt-metersdiy motor tips&tricksCumulus MFC
Last edited by Ron van Sommeren; Sep 19, 2019 at 08:55 AM.
Sep 19, 2019, 05:49 AM
Sure, I can fly after sunset!?
Something else to be aware of.

The higher the C rating, the heavier and bigger the battery.

This is true for most batteries. The only exception I’ve found is Venom. My 1300 mAh 3S Venom battery is smaller than any other such battery that I have. It is smaller than my eflight batteries and much smaller than another battery I just bought.

This could be important if the battery makes your plane nose heavy with the pack as far back as it can go.

This is also important if you have a small battery compartment. I just bought a 3 S 1300 mAh battery 70C and it will not fit into the battery compartment of my grandson’s Super Cub S.
Sep 19, 2019, 06:04 AM
Sure, I can fly after sunset!?
Here are two 1300 mAh 3S batteries. Different brands, different C ratings. Notice the huge difference in size.
Sep 19, 2019, 06:58 AM
Flying a Falcon or a 3D model.
fauconnier's Avatar
It is common for the batteries company to cheat on the C ratings but it's highly possible that some of them also cheat on the Amp. When a battery is a lot smaller than it should, like the red one, the Amp. could have been exaggerated also.
Sep 19, 2019, 07:52 AM
A man with too many toys
C rating was originally used to calculate the maximum current you could use to safely totally discharge a battery without harming it. That drove the size of the wires and connector. Now days it's just a mad-up marketing number that is mostly useless.

The higher the C the higher the price. Just double the C rating and double the price and everyone thinks they are getting a better battery.

.


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question Big Lipo battery charging small lipo battery and charger question... darkstar826 Beginner Multirotor Drones 7 Oct 25, 2017 08:11 AM
Discussion Best place to buy lipo. Online or shop? Sonic69 Singapore 1 Nov 26, 2016 05:09 AM
Question Shop where i can buy Lipo Batteries in Singapore swashplates Singapore 2 Feb 27, 2012 11:49 PM