Same specs but different brands of lipos running in series?

[RC MAN]

Hi everyone!

I recently have brought a motor that was rated for 19v so i should be able to run it on 5s. There aren’t many 5s batterys out there that are decently light and meet the specs that i need from a battery, so the only logical thing to do is run a 2s and 3s in series. I found a few options from battery’s that are from the same brand but most are pretty heavy, so the best combo i found that was relatively light weight and meet the specs that i need was a zeee 5200mah 100c 3s and a cnhl 5200mah 100c 2s.

So i am really just wondering if those two batterys would be ok to run in series

Cheers,

 

[nino]

It should work, but I'd just run it 4s or 6s and hope for the best.
Also, some ESCs won't arm on 5s because they see it as a discharged 6s, so you have to turn off LVC.

 

[RC MAN]

It should work, but I'd just run it 4s or 6s and hope for the best.
Also, some ESCs won't arm on 5s because they see it as a discharged 6s, so you have to turn off LVC.

I have it paired up with a mmx8s which does have a 5s LVC and i am not too keen on running past the recommend voltage (i am pushin it with 5s cuz fully charged 5s is 21v) but anyways it’s good to know that two different brands of battery can run in series. I guess i have a bit of head room in terms of max amp draw in my batterys... So if one battery has a slightly lower c rating than the other it will still probably have enough amp draw capabilities to keep up with the faster discharging one.

 

[pug]

Gens makes some 5s LiPos, I don't recommend running a 2s and 3s in a series. Here's the LiPo.

 

[nino]

Sorry, I just realised you mentioned two different brands. Don't do it. Just get a 5s battery or run 4s. Keep it simple.

 

[RC MAN]

Thanks for the responses

That gensacearespammers battery does not cut the mustard because i need a 5s 5000mah 80-100c battery. So i guess i can run cnhl 5200mah 100c 2s and a cnhl 5200mah 100c 3s and just have to save weight somewhere else.... So why would you guys not recommend running a 2s and a 3s in series if that’s the only choice?

 

[pug]

Thanks for the responses

That gensacearespammers battery does not cut the mustard because i need a 5s 5000mah 80-100c battery. So i guess i can run cnhl 5200mah 100c 2s and a cnhl 5200mah 100c 3s and just have to save weight somewhere else.... So why would you guys not recommend running a 2s and a 3s in series if that’s the only choice?

No, I wouldn't recommend it. Also, the highest C rating LiPo that I have seen is only 40C max! CNHL LiPos aren't even true 100c, most likely 35 - 40c, the 5s would work just fine.

 

[WickedFog]

Agreed. Most C ratings on batteries are pretty bloated. I run lots of cars on batteries with C ratings lower than recommended and they do just fine. And there used to be some tests here showing even high end batteries don't actually come close to their advertised C rating.

 

[nino]

You can probably get a 6s rated motor for the money you'll spend on 5s batteries or a 2s/3s combo.

 

[RC MAN]

Ok, thanks for info guys

Why isn’t it recommend that you run a 2s and a 3s in series to make 5s.... Also at full throttle i could be pulling 350-400-450 amps so i need a battery that can preferable sustain 450 amps without puffing and blowing up.... so would something like the HRB 5200mah 50c 5s or that genes ace battery be able to handle that sort of amp draw?

No, I wouldn't recommend it. Also, the highest C rating LiPo that I have seen is only 40C max! CNHL LiPos aren't even true 100c, most likely 35 - 40c, the 5s would work just fine.

So aren’t CNHL batterys actually the advertised c rating... i thought that a lot of people who do speed runs use CNHL batterys and that they are even their preferred battery to use?

 

[WickedFog]

Ok, thanks for info guys

Why isn’t it recommend that you run a 2s and a 3s in series to make 5s.... Also at full throttle i could be pulling 350-400-450 amps so i need a battery that can preferable sustain 450 amps without puffing and blowing up.... so would something like the HRB 5200mah 50c 5s or that genes ace battery be able to handle that sort of amp draw?

So aren’t CNHL batterys actually the advertised c rating... i thought that a lot of people who do speed runs use CNHL batterys and that they are even their preferred battery to use?

The highest C rating of any battery in Grey's testing was less than 40C. And some of the batteries were over 100C advertised if I remember correctly. The CNHL was some of the higher scores, but by no means did they come close to their advertised rating. Liperior batteries were actually better performers I believe.

 

[WickedFog]

Apparently, as long as the C rating and mAh of the two mismatched batteries is the same, you can run mismatched cell counts. In theory, wiring them in series is no different than buying s 5s pack. But a conflicting report from Greywolf said he smoked two 2s packs when trying to run a 4s snd 2s together.

https://www.rctech.net/forum/electric-off-road/338642-running-2-lipo-packs-series-parallel.html#:~:text=You are able to run,is similar as mentioned before.

If you run a LiPo alarm on the packs, you wouldn't have anything to worry about. Whichever pack drains first will alert you. If I were to try this I would make sure the IR of the batteries were very close to each other as well.

 

[nino]

Yes, check that the IRs are close and make sure you run lipo alarms on both packs. That is, if you decide to go against the recommendations of everyone here

 

[RC MAN]

Ok, thanks for the advise

So would anyone be able to recommend a good 5s battery or 3s/2s combo for the price? ( and preferably around the 5000mah mark) or would the cnhl battery combo i mentioned earlier be the best option?

Also if anyone has the link to grey’s lipo testing that would be awesome!

cheers,

 

[pug]

Ok, thanks for the advise

So would anyone be able to recommend a good 5s battery or 3s/2s combo for the price? ( and preferably around the 5000mah mark) or would the cnhl battery combo i mentioned earlier be the best option?

Also if anyone has the link to grey’s lipo testing that would be awesome!

cheers,

I can't find the thread, I hope it wasn't deleted. But here is a fairly priced CNHL 5s.

 

[WickedFog]

The LiPo thread was deleted. If it were me, I would buy the cheapest 3s and 2s you could to test this on. Grey said he tried it twice, thinking the first time was a fluke, and he fried two 2s packs. I would be leery of trying this just because he said not to.

If it were me actually though, I would just buy a 6s capable motor, or run it on 4s and gear accordingly. A lot can be done with gearing to get a car running the way you want, and keep the motor in check with regards to heat.

If you do go with the CNHL 3s and 2s packs, I would run the car for a minute and check the drain on each pack. Then run it for another minute and check them again. If it looks like one is draining faster, I'd stop.

 

[RC MAN]

Ok, will do guys!

So if the cnhl 5000mah 5s 40c is less the advertised c rating that they state (40c) and if the cnhl 2s/3s 100c 5200mah isn’t truely 100c like they say either... would that mean that they would work out to be around the same true c rating (or would it just be that the 2s/3s are rated at a stated 100c, so they would have a higher true c rating than the stated 40c ones?)


(And yes i will probably not run a 2s and 3s in series if grey fried two packs, running a 4s and 2s of the same brand of lipo in series.)

 

[pug]

Ok, will do guys!

So if the cnhl 5000mah 5s 40c is less the advertised c rating that they state (40c) and if the cnhl 2s/3s 100c 5200mah isn’t truely 100c like they say either... would that mean that they would work out to be around the same true c rating (or would it just be that the 2s/3s are rated at a stated 100c, so they would have a higher true c rating than the stated 40c ones?)

I'm guessing that the 40c is around 30-35c and the 100c is 35-40c.

 

[RC MAN]

I'm guessing that the 40c is around 30-35c and the 100c is 35-40c.

WOW..... how did CNHL get 100C ?
And why is the 40c so conservative compared to the 100c?

Also Wouldn't the 2s/3s be even less than 35-40c because of all the extra wiring i have to do to run them in series?

 

[pug]

WOW..... how did CNHL get 100C ?
And why is the 40c so conservative compared to the 100c?

Also Wouldn't the 2s/3s be even less than 35-40c because of all the extra wiring i have to do to run them in series?

It would be the same C-rating, but the extra wiring adds some resistance.