Question regarding LiPo batteries.

[Randy Barron]

I'm not sure if this is the proper thread for this, if this isn't, I'll apologize in advance.

That being said, I've just got back into the RC PLANE hobby. The last time I was doing this, everything was using fuel for power. This time I'm using batteries. After doing a lot of reading, I have a few (I hope) simple questions regarding them. I'm just really looking for confirmation that what I intend on doing is actually fairly reasonable.

1. I'm using a 3s LiPo pack. From everything I'm reading, the safe discharge voltage would be 9.0 V (3.0 V/cell). I don't intend on running them that low. I'm wondering if setting my telemetry alarm to 9.9 V (3.3 V/cell) would this cause an issue? Is this too low, too high, correct?

2. Maximum charge will be 12.6 V (4.2 V/cell). Is this correct?

3. Storage voltage should be between 11.1 V (3. 7 V/cell) and 11.4 V (3.8 V/cell).

4. I'm using the Spektrum NX7e+, I set the alarm on it for the low voltage alarm....correct? (yes, I know that was a silly question).

Any help or advice you could give would be INCREDIBLY appreciated.

 

[Yardbird]

I have always been told not to go below 3.4, but know some who do. Storage 3.85

 

[biggman100]

I am very, very particular about lipo's, and, after having a house fire that may or may not have been related to improper handling of them, and, have since learned some hard rules about. Never discharge below 3.4V per cell, always storage charge at 3.8-3.9V per cell, and, always check with a battery monitor every week that they are being stored.

 

[RustyUs]

Good info... http://www.rogershobbycenter.com/lipoguide/
I set my low voltage cutoffs (LVC) to 3.5v/cell on my ESCs.... most of the time. Some ESCs differ in the ending voltage/sensitivity so I watch/check voltages when when LVC kicks in for the first couple of runs on a new ESC and adjust LVC setting from there. Some of my LVC are set to 3v/cell but in actuality the LiPo cells are at 3.4~3.5v when I check the voltages.

Welcome to the forum!

Anything "electrical" subforum category... Electronics

 

[Randy Barron]

I have always been told not to go below 3.4, but know some who do. Storage 3.85

Thanks you!

Good info... http://www.rogershobbycenter.com/lipoguide/
I set my low voltage cutoffs (LVC) to 3.5v/cell on my ESCs.... most of the time. Some ESCs differ in the ending voltage/sensitivity so I watch/check voltages when when LVC kicks in for the first couple of runs on a new ESC and adjust LVC setting from there. Some of my LVC are set to 3v/cell but in actuality the LiPo cells are at 3.4~3.5v when I check the voltages.

Welcome to the forum!

Anything "electrical" subforum category... Electronics

That was FANTASTIC information. It cleared up a lot of my questions. Thank you!!!

I am very, very particular about lipo's, and, after having a house fire that may or may not have been related to improper handling of them, and, have since learned some hard rules about. Never discharge below 3.4V per cell, always storage charge at 3.8-3.9V per cell, and, always check with a battery monitor every week that they are being stored.

Thank you!

 

[paytonimusrex]

you should definitely get a lipo bag I may or may not have one and have been raw dogging it with charging

 

[Lukedavis]

Also check your batteries before every run because just yesterday almost had a Lipo fire. I was running my rusty 4x4 on 4s and it started cutting out and one of my 2s was super warm so I took it out and put it on the balance charger to check voltage. Come to find out, one cell was at 3.7 volts and the other was at 3.2. I then noticed that there was an odd bulge at the corner of the Lipo. I had the battery wrapped in electrical tape before hand so I unwrapped it all, and sure enough one of the cells was split in 2. As soon as I unwrapped it it started smoking so I threw it outside of the garage.

 

[tntpoof]

get a lipo safe ..aka charge bag. I always liked a ammo can myself...
and your storage voltage is to low..try not to take a lipo below...3.9 volts a cell... a simple lipo buzzer is best on battery in plane...

 

[paytonimusrex]

do yall store your lipos all in a bag or only charge them in a bag? I need to get something figured out for mine

 

[DavidB1126]

I store in a bag. I also charge in smaller bags at the track since they require them

I'm using Amazon backs. Branded hoovo. The bigger one to store my charger and leads. Smaller one for batteries. And then for charging sacks I use smaller Tenergy bags with Velcro tops.

 

[paytonimusrex]

cool thanks i’ll have to look at some from amazon, I see people say ammo cans but how well do those actually work cause i’ll get one

 

[DavidB1126]

Ammo can would be better than Amazon bags. Most likely. I just use Amazon bags so I can take my stuff back and forth to the track.

 

[CertifiedMike]

I am learning lio too! @Greywolf74 is our forum authority on lipos.
Hopefully he can point you in some good directions to solve your questions.

Something metal will be better to handle a battery that has already ignited when you need to get it to a safe location. The thing that sux about these batteries is that in order to handle them correctly, safely, they each need their own container.
If all your batteries are in 1 box, yes they are in a centralized location but if 1 goes up, so do they all.
Thats the most important thing I think. Proper handling, storage and use.

 

[paytonimusrex]

how about their own bags all stored in ammo can

 

[DavidB1126]

how about their own bags all stored in ammo can

Then if so, you are extra safe

 

[paytonimusrex]

Then if so, you are extra safe

sounds like I gotta hit up an army navy story then lol

just watched some videos on different storing with ammo can looks like ammo can and bags is the way to go then

 

[CertifiedMike]

Ppl make plastic sand bags to put over top. (leave room for air etc obviously)
If you get too hot it will melt the bag and help to suffocate flames at least til you get yourself and it someplace safe!

 

[paytonimusrex]

well that’s an idea, lipos won’t really go off though when just sitting

 

[CertifiedMike]

I'm not super experienced with lipos. I just mentioned it while we were talking about the ammo boxes.
I thought they were charging in the box too but I may have that wrong.

My experience is in a salvage yard with an acetylene torch and very hot mrtals.
Thankfully and hopefully, NEVER fire!

 

[paytonimusrex]

I have no idea I know charging is in a bag but idk anything beyond that