Redcat Landslide and NIMH batteries???2 min runtime???

[Cleaning Goblin]

Hi, I have a redcat Landslide with two brand new NIMH batteries. I am using NIMH because they are generally safer and my father has had multiple LIPO fires lately.

The NIMH batteries (2x 7.2V 8c 3200Mah) appear to be better on paper than my old LIPOs, but they die in about 2 minutes from a full charge.

This truck uses two batteries in series.

Is there any way I could limit the insanely fast draining of the batteries just to get some more runtime? Tomorrow is homecoming and I want to take the Landslide for a little spin.

Thanks a lot ^^

 

[F.R.S. Ninja_007]

NimHs are great for small trucks like my Merv (although I still want a LiPo for it), but for a 4S vehicle, not so much. Does the ESC even have a NimH mode? You should just use LiPo; learn to take good care of your batteries, get a reputable brand of batteries and chargers. I’m sure @Greywolf74 will have some info for you.

 

[Cleaning Goblin]

NimHs are great for small trucks like my Merv (although I still want a LiPo for it), but for a 4S vehicle, not so much. Does the ESC even have a NimH mode? You should just use LiPo; learn to take good care of your batteries, get a reputable brand of batteries and chargers. I’m sure @Greywolf74 will have some info for you.

It does have a NIMH mode, and even says in the manual what kind of NIMH or LIPO it will need for which specific motor and weight

These batteries should meet the requirements as far as I know

(using LIPOs is not convenient for me because of the danger due to my living conditions. Am I completely out of luck?)

 

[tntpoof]

sorry your outa luck. did you condition the nixx b4 use? you need 2 steel buckets one with sand 1/4 filled the other half filled for a fire control. why did you dad have lipo fires? i used nicad nimh way back in the days I will never use them again .I've had a good run with lipos no fires I dont buy cheap china brands I buy good brand I feel safe with 15 years greater run time more fun no worries

 

[tudordewolf]

Hi, I have a redcat Landslide with two brand new NIMH batteries. I am using NIMH because they are generally safer and my father has had multiple LIPO fires lately.

The NIMH batteries (2x 7.2V 8c 3200Mah) appear to be better on paper than my old LIPOs, but they die in about 2 minutes from a full charge.

This truck uses two batteries in series.

Is there any way I could limit the insanely fast draining of the batteries just to get some more runtime? Tomorrow is homecoming and I want to take the Landslide for a little spin.

Thanks a lot ^^

Is the low voltage cutoff intended for lipos still enabled on the ESC? NiMh batteries are more prone to voltage drop under load, and it could be triggering the low voltage protection while the batteries are still mostly full. You'll need to move a jumper on the ESC to set it, or in this case disable it.

NiMh batteries continued to improve even as lithium eclipsed them, modern stick packs are 2-3 times more potent than "old school" 7.2V packs which only had 1200mah, and people ran those hard in races. It would take a lot to kill one in under 5 minutes...

(edit): But... the landslide has a 120A ESC. If it's trying to pull 100A surges from those packs, it may very well be emptying them in 2-3 minutes. NiMhs deliver fewer mAh the harder you drain them, one of their biggest weaknesses compared to lipos, which deliver 90%+ of their rated mAh capacity even at max drain.

 

[Cleaning Goblin]

sorry your outa luck. did you condition the nixx b4 use? you need 2 steel buckets one with sand 1/4 filled the other half filled for a fire control. why did you dad have lipo fires? i used nicad nimh way back in the days I will never use them again .I've had a good run with lipos no fires I dont buy cheap china brands I buy good brand I feel safe with 15 years greater run time more fun no worries

View attachment 172386

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View attachment 172388

We are not sure what caused the fires, and I've never heard of conditioning batteries so that could be one thing

Is the low voltage cutoff intended for lipos still enabled on the ESC? NiMh batteries are more prone to voltage drop under load, and it could be triggering the low voltage protection while the batteries are still mostly full. You'll need to move a jumper on the ESC to set it, or in this case disable it.

NiMh batteries continued to improve even as lithium eclipsed them, modern stick packs are 2-3 times more potent than "old school" 7.2V packs which only had 1200mah, and people ran those hard in races. It would take a lot to kill one in under 5 minutes...

(edit): But... the landslide has a 120A ESC. If it's trying to pull 100A surges from those packs, it may very well be emptying them in 2-3 minutes. NiMhs deliver fewer mAh the harder you drain them, one of their biggest weaknesses compared to lipos, which deliver 90%+ of their rated mAh capacity even at max drain.

Low voltage cutoff is off

Yeah that makes sense

 

[tudordewolf]

We are not sure what caused the fires, and I've never heard of conditioning batteries so that could be one thing

Low voltage cutoff is off

Yeah that makes sense

I've capacity tested both individual NiMh cells and packs, and the conditioning effect is definitely a factor.

I get something like 50%, 75%, and then 95% capacity from brand new batteries just doing 3 charge / discharge cycles. Many smart chargers build that in as a "refresh" function.

 

[tntpoof]

My charge and carry to rc locations are as follows

red one .Original Bat box from 2014 or so paid $7 usd
Hot Tomales lunch box.has fireproof orange material in it good to 3000 degrees f
Non burning fire proof ammo can with smoke heat detector and fire proof cloth all my charging boxes have vent holes
see I take My safety seriously and those around me.I also have my 2 steel buckets with sand in hand
if you decide to go to lipo make sure you gear your rc for lipo. large pinions
I state things 99% from personal experiences my Futaba cdr 5000 is still used these days


to condition a new nixx (goes for all Nickle packs)

1. what is chargers lowest charge level? hopfully below a 1/4 amp
charge battery at that amount (dont leave a batty for any reason)
I can go down to 1/10 of a am

2. Discharge battery at as close to wanted amperage as possible

3. charge battery at 1 amp

4. Discharge like step 2

5. you then do this in 1/4 amp intervals until you get to final charge amount. Sure it takes time but well worth it in the End for life and performance of pack. Till that one cell dies and you retire or whatever to pack

 

[Cleaning Goblin]

My charge and carry to rc locations are as follows

red one .Original Bat box from 2014 or so paid $7 usd
Hot Tomales lunch box.has fireproof orange material in it good to 3000 degrees f
Non burning fire proof ammo can with smoke heat detector and fire proof cloth all my charging boxes have vent holes
see I take My safety seriously and those around me.I also have my 2 steel buckets with sand in hand
if you decide to go to lipo make sure you gear your rc for lipo. large pinions
I state things 99% from personal experiences my Futaba cdr 5000 is still used these days


to condition a new nixx (goes for all Nickle packs)

1. what is chargers lowest charge level? hopfully below a 1/4 amp
charge battery at that amount (dont leave a batty for any reason)
I can go down to 1/10 of a am

2. Discharge battery at as close to wanted amperage as possible

3. charge battery at 1 amp

4. Discharge like step 2

5. you then do this in 1/4 amp intervals until you get to final charge amount. Sure it takes time but well worth it in the End for life and performance of pack. Till that one cell dies and you retire or whatever to pack

View attachment 172409

One of the batteries ended up getting very hot and melting the soft plastic casing during the charge cycle, but still functions normally. I'm not sure what happened, but the batteries are performing a bit better now

 

[tudordewolf]

One of the batteries ended up getting very hot and melting the soft plastic casing during the charge cycle, but still functions normally. I'm not sure what happened, but the batteries are performing a bit better now

Sounds like the charger missed the end of charge and kept putting current into it. NiMh's are pretty durable fortunately. What kind of charger are you using?

 

[Cleaning Goblin]

Sounds like the charger missed the end of charge and kept putting current into it. NiMh's are pretty durable fortunately. What kind of charger are you using?

It's a generic smart charger, called a b6 lipro charger

 

[tudordewolf]

It's a generic smart charger, called a b6 lipro charger

I have the very same. It has a port for a temperature probe that costs about $5. Look up the SkyRC temperature sensor. You can set a cutoff that terminates the charge if the batteries get too hot. The way NiMhs work, that's a very reliable way to halt the charge anyway, they only start to really warm up once they're full if you're charging them at a reasonable (~1C or below) rate.