Switching Batteries

[BsudRC]

I wanting to switch over to NiMh batteries, In my TRX4, Mojave 4s, and Tekno DB48. I know the cars Will not go as fast as lipo but that doesn't bother me cause I could care less if they go 50+ mph. As long as they go pretty Fast and I get some long Run times that's all that matters to me. With that said What are some Strong Long Run Time NiMh batteries I could get?

 

[DavidB1126]

Nimhs can't hold up and take the load of modern brushless systems. Best bet is to stay with lipos.

 

[9x19]

I wanting to switch over to NiMh batteries, In my TRX4, Mojave 4s, and Tekno DB48. I know the cars Will not go as fast as lipo but that doesn't bother me cause I could care less if they go 50+ mph. As long as they go pretty Fast and I get some long Run times that's all that matters to me. With that said What are some Strong Long Run Time NiMh batteries I could get?

You'll want a 7 cell, 8.4v... then the largest mAH rating you can find, then get two, you'll probably need them for a decent run time... to start you off, look for something like these

https://www.amazon.com/gp/product/B0D7MMWWH4/ref=ox_sc_act_title_1?smid=A1KODDOPEPALCP&psc=1

 

[RustyUs]

Battery bars, and shrink wrap... there is always the option to build your own packs, but for running larger 1/8 scale RCs, I ask the question, why even try? Finding 12~14 cell NiMh packs premade; that fit into a normal battery tray... good luck. It's been so long since I've used any 6/7cell NiMh packs, I'd be worried the load handling capabilities of them, in conjunction with heavier RCs... I don't see good things happening.

It sounds like you had bad experiences with LiPo batteries. That's the only conclusion I can wrap around my head for "switching batteries". What have you been using for your 1/8 scale Mojave and DB48 RC platforms?

 

[BsudRC]

Battery bars, and shrink wrap... there is always the option to build your own packs, but for running larger 1/8 scale RCs, I ask the question, why even try? Finding 12~14 cell NiMh packs premade; that fit into a normal battery tray... good luck. It's been so long since I've used any 6/7cell NiMh packs, I'd be worried the load handling capabilities of them, in conjunction with heavier RCs... I don't see good things happening.

It sounds like you had bad experiences with LiPo batteries. That's the only conclusion I can wrap around my head for "switching batteries". What have you been using for your 1/8 scale Mojave and DB48 RC platforms?

Yes had a bad experience and now I'm scared of them. It's not a pretty sight when one goes up!

 

[Greywolf74]

Yes had a bad experience and now I'm scared of them. It's not a pretty sight when one goes up!

There are steps you can take to protect yourself with LiPos. I don't think you'll be happy with the performance or longevity that NiMH is going to give you but if you're determined to go that route, then find the highest cell count (within ESC/motor tolerances) and the highest mAh rating you can find that will still fit in your battery tray as 9x19 mentioned.

 

[BsudRC]

There are steps you can take to protect yourself with LiPos. I don't think you'll be happy with the performance or longevity that NiMH is going to give you but if you're determined to go that route, then find the highest cell count (within ESC/motor tolerances) and the highest mAh rating you can find that will still fit in your battery tray as 9x19 mentioned.

What are the steps to take to help protect? I mean I never charge them without being in a Bag, I only store them at 50%. I don't know what else to do

 

[Greywolf74]

What are the steps to take to help protect? I mean I never charge them without being in a Bag, I only store them at 50%. I don't know what else to do

For instance, if someone was super concerned, they could only charge lipos outside, inside something like an ammo can while also putting the battery inside a lipo bag. Then if anything goes wrong, no problem. Of course, the issue you run in to here in charging lipos in the winter if you live somewhere that's freezing. If you live in the southern part of the US, for example, no problem. You don't want to be charging lipos in 35F or lower weather.

If you're a little braver, you can charge lipos inside your house, just get a paver to set your ammo can on and still use a lipo bag also. Also, make sure that the ammo can isn't right next to something that can catch fire. This way, if you have a lipo fire, then the only thing you have to worry about is the smell in your house. Using the ammo can may even allow you to carry the lipo outside during the initial thermal runaway phase if you catch it early enough.

P.S. Just make sure you drill a small vent hold in the ammo can in the event you need to close and seal the lid to carry it outside while the lipo is venting. Bear in mind, you don't want that hole facing straight up or on one of the sides, in case you need to try and carry it. I typically put my vent hole in the front so that way if it vents it won't be venting toward the wall and again, if I have to carry it, it won't be venting toward me either.

 

[BsudRC]

For instance, if someone was super concerned, they could only charge lipos outside, inside something like an ammo can while also putting the battery inside a lipo bag. Then if anything goes wrong, no problem. Of course, the issue you run in to here in charging lipos in the winter if you live somewhere that's freezing. If you live in the southern part of the US, for example, no problem. You don't want to be charging lipos in 35F or lower weather.

If you're a little braver, you can charge lipos inside your house, just get a paver to set your ammo can on and still use a lipo bag also. Also, make sure that the ammo can isn't right next to something that can catch fire. This way, if you have a lipo fire, then the only thing you have to worry about is the smell in your house. Using the ammo can may even allow you to carry the lipo outside during the initial thermal runaway phase if you catch it early enough.

P.S. Just make sure you drill a small vent hold in the ammo can in the event you need to close and seal the lid to carry it outside while the lipo is venting. Bear in mind, you don't want that hole facing straight up or on one of the sides, in case you need to try and carry it. I typically put my vent hole in the front so that way if it vents it won't be venting toward the wall and again, if I have to carry it, it won't be venting toward me either.

Well we've been having some really cold weather here in SC. I haven't ran them in quite some time. They are in my lipo bag in my Building so they have been sitting in Cold temps this winter but they are at 50% When I store them. I never charge inside my home nor do I bring them inside my home. And I always charge them in my lipo bag outside

 

[Greywolf74]

Well we've been having some really cold weather here in SC. I haven't ran them in quite some time. They are in my lipo bag in my Building so they have been sitting in Cold temps this winter but they are at 50% When I store them. I never charge inside my home nor do I bring them inside my home. And I always charge them in my lipo bag outside

Storing your LiPos under 50F is not good for the LiPos. Other than that though, if you're only charging them outside then what's the problem? If one goes up, then you're only out a battery and possibly a charging/balancing cable. Not trying to talk you out of NiMH packs, as they will work OK in a crawler, but the run times won't be as long as a LiPo. I'm just curious because I don't understand your hang-up about LiPos.

 

[LowCountryCrawl]

Lipos can be scary but, your taking all the precautions you can and need to. I would just order some new lipos from amazon or hobbyking and let it rip. Would love to meetup sometime since I'm in SC also but close to GA in Beaufort.

 

[BsudRC]

Lipos can be scary but, your taking all the precautions you can and need to. I would just order some new lipos from amazon or hobbyking and let it rip. Would love to meetup sometime since I'm in SC also but close to GA in Beaufort.

Well my 4s lipos are fairly new Maybe only a year old. I don't keep them in the house so I have to store them in my Building And at times it's well below 50° Degrees in there. I do keep them in the lipo bag which I'm sure helps to keep them warmer.
Btw I'm in Upstate SC

 

[Greywolf74]

Well my 4s lipos are fairly new Maybe only a year old. I don't keep them in the house so I have to store them in my Building And at times it's well below 50° Degrees in there. I do keep them in the lipo bag which I'm sure helps to keep them warmer.
Btw I'm in Upstate SC

This is something I posted in another thread about someone asking about storage temps for lipos. This is just something to be aware of, since you might be setting yourself up for another future failure.



"The damage is being done when they are sitting there below freezing. Not warming them up first will damage them even faster, but you're not doing your batteries any favors by leaving them outside when its below 60F let alone below freezing. This is why I don't keep my lithium tool batteries outside in the garage anymore in the winter. I got tired of replacing them every couple/few years.

FYSA:
Storing LiPo batteries below freezing temperatures can lead to several internal changes that may compromise their performance, longevity, and safety.

Internal Changes Due to Freezing:

1. Lithium Plating:
   
   • At temperatures below 0°C (32°F), lithium ions may deposit as metallic lithium on the anode instead of intercalating into the graphite structure.
   • This metallic lithium can form dendrites—needle-like structures—that penetrate the separator between the anode and cathode, increasing the risk of internal short circuits and potential thermal runaway.
2. Electrolyte Freezing:
   
   • Extreme cold can cause the electrolyte to freeze, leading to increased internal resistance and reduced ion mobility.
   • This results in diminished capacity, voltage output, and overall performance.
3. Structural Stress:
   
   • The contraction of internal components due to freezing temperatures can induce mechanical stress, potentially leading to micro-cracks in electrodes or separators.
   • Such damage can degrade battery integrity and safety over time."

 

[BsudRC]

This is something I posted in another thread about someone asking about storage temps for lipos. This is just something to be aware of, since you might be setting yourself up for another future failure.



"The damage is being done when they are sitting there below freezing. Not warming them up first will damage them even faster, but you're not doing your batteries any favors by leaving them outside when its below 60F let alone below freezing. This is why I don't keep my lithium tool batteries outside in the garage anymore in the winter. I got tired of replacing them every couple/few years.

FYSA:
Storing LiPo batteries below freezing temperatures can lead to several internal changes that may compromise their performance, longevity, and safety.

Internal Changes Due to Freezing:

1. Lithium Plating:
   
   • At temperatures below 0°C (32°F), lithium ions may deposit as metallic lithium on the anode instead of intercalating into the graphite structure.
   • This metallic lithium can form dendrites—needle-like structures—that penetrate the separator between the anode and cathode, increasing the risk of internal short circuits and potential thermal runaway.
   • Extreme cold can cause the electrolyte to freeze, leading to increased internal resistance and reduced ion mobility.
   • This results in diminished capacity, voltage output, and overall performance.

I understand that But I don't think after my experience I'm brave enough to leave those batteries in my house! If I knew of a way to keep them warmer in my detached Garage I would do so. Any ideas?