What's the proper way to charge a 9000 mah battery

[38super]

Hi All
Up till now I have never had a problem charging a battery that's because they were at or under 5000mah.
As I understand it if you have a 3300mah batt at 11.1 v you just set your charger at 3.3A and 11.1v and start to charge. But now I have a Max Amp 9000xl 14.8V 100c battery. I can't set my charger a 9A because it only goes to 5A
I called Max Amp they told me to go into( user set program) on my I Max B6 and set capacity cut-off to 9000mah.
At first I thought it would bring up my amps but still 5A is as far as it will go. I have not tried this yet as far as charging but what will this do in charging a large lipo . I posted problems I've had trying to charge this battery .
one was connection break and another was a CAPA flashing on my display . Had to start charging over after each interruption and eventuallyI got full charge. How do you guys with these large lipos charge them . Max Amps said my charging system was fine ..... It may just be a bad battery . Will find out soon cause I just ordered another one
William

 

[Matt Sharp]

You're not actually doing anything wrong. The imax B6 is only capable of delivering 5 amps. You're at it's limit.

If you're wanting to be able to charge at 1c, or even more, then you'll need to invest in a new charger. I've used many over the last 10 years, but my favorites are the icharger line. You'll need an external power supply to power the charger, but it will allow you to charge much larger batteries in less time.

 

[RichardDoty]

You can charge it at 4.5A or 5A, and it make sense, just need more time to fully charge your 9000mAh lipo packs.
P.S charge less than 1C won't do harm to your lipo, just cost more time.

Or get a new balance charger with higher output current and consumption power like Matt suggested.

 

[AlienNet]

interesting post, sorry to break in, i have a new 10000mah 4s Lipo, so is it safe to charge at 6a even though it takes longer ?
Thanks.

 

[fltundra]

interesting post, sorry to break in, i have a new 10000mah 4s Lipo, so is it safe to charge at 6a even though it takes longer ?
Thanks.

Absolutly, I have the 10ah10c Multistar 4S and up until today i have been charging at .4 C with no problems.

 

[AlienNet]

Hi Thanks for the quick reply, my lipo is also a Multistar 10c 4s and i am intending to charge it with a Turnigy accucell 6 Charger which has a max current of 6a, i dont mind waiting for it to charge, i often heard that a slow charge was a better charge ??

 

[38super]

Just to get back to my original thread. My batteries are way over kill for my F550 100c rating I can charge at 20 amps from a cell count of 3.70v 4s , that's as low as I go per cell on most of the time on a maxamps 9000xl.
Only thats 30 mins and I'm back in the air . I have two . If I push them say to 3.45 v I get 20 min flight time and about 40 charge time I can go all days with just a few mins in between charges with two batteries

 

[fltundra]

Just to get back to my original thread. My batteries are way over kill for my F550 100c rating I can charge at 20 amps from a cell count of 3.70v 4s , that's as low as I go per cell on most of the time on a maxamps 9000xl.
Only thats 30 mins and I'm back in the air . I have two . If I push them say to 3.45 v I get 20 min flight time and about 40 charge time I can go all days with just a few mins in between charges with two batteries

Your killing them slowly discharging them to that low of voltage. My lipos end up at at around 3.68v under load at 80% discharge, 3.7-3.74 at rest.

 

[gtranquilla]

100C rated battery is a bit on the overkill and heavy side relative to a 35C.
And two smaller capacity 25 or 35C batteries will provide excellent results since two 35C batteries in parallel is equal to 70C.

Hi All
Up till now I have never had a problem charging a battery that's because they were at or under 5000mah.
As I understand it if you have a 3300mah batt at 11.1 v you just set your charger at 3.3A and 11.1v and start to charge. But now I have a Max Amp 9000xl 14.8V 100c battery. I can't set my charger a 9A because it only goes to 5A
I called Max Amp they told me to go into( user set program) on my I Max B6 and set capacity cut-off to 9000mah.
At first I thought it would bring up my amps but still 5A is as far as it will go. I have not tried this yet as far as charging but what will this do in charging a large lipo . I posted problems I've had trying to charge this battery .
one was connection break and another was a CAPA flashing on my display . Had to start charging over after each interruption and eventuallyI got full charge. How do you guys with these large lipos charge them . Max Amps said my charging system was fine ..... It may just be a bad battery . Will find out soon cause I just ordered another one
William

 

[SleepyC]

Yea, I mean you could charge at.01 amp and it would be fine. It would take a year, but it would be fine.

 

[Tuomas P.]

Never go under 3.55 V per cell under load.
TP.

 

[Quinton]

100C rated battery is a bit on the overkill and heavy side relative to a 35C.
And two smaller capacity 25 or 35C batteries will provide excellent results since two 35C batteries in parallel is equal to 70C.

Sorry for asking this, but what I have learned in the short time I have been trolling the mad world of the internet for answers, 2x35C batteries in parallel does not give you 70C.
"C" rating is based on the storage capacity of the lipo and the amount of current it can produce.
You would not double the c rating, only the capacity please correct if I am wrong.

 

[gtranquilla]

Quinton,
I was going from memory on the basis of previous comments here on MRF from others without digging in to the calculations.
Obviously the maH doubles with batteries wires in parallel..... but the C rating????

I think we need more input from others....in the meantime here is some very good information that almost provides an answer. http://www.maac.ca/docs/2013/lipo_b...e_max_current_draw_true_crating__rev3_toc.pdf





Sorry for asking this, but what I have learned in the short time I have been trolling the mad world of the internet for answers, 2x35C batteries in parallel does not give you 70C.
"C" rating is based on the storage capacity of the lipo and the amount of current it can produce.
You would not double the c rating, only the capacity please correct if I am wrong.

 

[Quinton]

Quinton,
I was going from memory on the basis of previous comments here on MRF from others without digging in to the calculations.
Obviously the maH doubles with batteries wires in parallel..... but the C rating????

I think we need more input from others....in the meantime here is some very good information that almost provides an answer. http://www.maac.ca/docs/2013/lipo_b...e_max_current_draw_true_crating__rev3_toc.pdf

Thanks for the link.
I have been a member here now for 1 year, and there is a LOT of useful information, but I think I can say that you should not believe 100% all the posts you read online, as a lot of it is hear-say, without actually sitting down and finding out if things are really true or not.
I am not trying to prove anyone wrong or right or make a point, if I come across that way in posts I apologise as most of the stuff I have learned has been from here and I did not have a clue about it a year ago.

Maybe I am wrong, but the way I see it is like this..

If I have a desire 6200 mAh 35C battery maximum Continuous current of 217A
Put 2 together it then turns into 12400 mAh battery at 35C which can draw 434A without damage.
If it was a 6200 mAh battery on its own and you could draw 434A then it would be a 70C, but its not it is now a 12400 mAh battery.
12.4*35 = 434A, you double the amperage you can draw, but the C rating stays the same.

I "believe".

 

[edgarmillennium]

100C rated battery is a bit on the overkill and heavy side relative to a 35C.
And two smaller capacity 25 or 35C batteries will provide excellent results since two 35C batteries in parallel is equal to 70C.

That is not exactly correct. If you have 2 5000 35C in parallel you will have 175 amps Discharge for each pack. 2 will be 350 amps. So because they are 5000 you will have 10,000 mamps. So together they will be 28.5 C. What it really happens is that the request for amps will be divided in two batteries.

 

[edgarmillennium]

SOrry I didn't saw somebody explained already.

 

[gtranquilla]

This getting a bit confusing...... I think we need more input from more experts.....and maybe even some detailed formula calculations. Anyone here on MRF able to add some more clarity?
[MENTION=1417]kloner[/MENTION]

That is not exactly correct. If you have 2 5000 35C in parallel you will have 175 amps Discharge for each pack. 2 will be 350 amps. So because they are 5000 you will have 10,000 mamps. So together they will be 28.5 C. What it really happens is that the request for amps will be divided in two batteries.

 

[Quinton]

That is not exactly correct. If you have 2 5000 35C in parallel you will have 175 amps Discharge for each pack. 2 will be 350 amps. So because they are 5000 you will have 10,000 mamps. So together they will be 28.5 C. What it really happens is that the request for amps will be divided in two batteries.

OK so I am also getting confused so are you saying..
5 (5000mAh)*35 = 175A max continuous current
Times 2 = 350A from 2 lipos

Then for you to get 28.5C you seem to be taking 10000 and dividing it by 350 to give your 28.5C?
Is it not still 350/10 = 35C?
This is why I say don't believe everything you read on the net

 

[kloner]

everything was right on till the 28.5c part....5 amp hours x 35c is 175 amp service

 

[edgarmillennium]

Well my main language is Spanish, so I will try to do my best in explain it in English. C ratings are a characteristic related directly with the chemistry and the internal resistance of the battery. So they can not be added. IS you want to calculate how much amp you can draw continuously on a battery, you multiply C x Capacity = Amp draw. For example, if you have one 5000 mah battery with 35C capacity will be 35 x 5 = 175 amps , If you have 2 parallel 5000 you will have 10,000 in capacity. But you can only draw a max amount of 175 per battery. If you multiply by 2, y will have the capacity of drawing of 350 amps. With this numbers you will have 350/10 35.

Sorry I made a mistake on m previous calculation trying to explain I will not be 70C