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Nikko85

Li-Ion Batteries

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Does anyone use Li-Ion batteries in their cars?

I've got a couple of cars running 3000 mAh 2s 18650 Li-Ions, which seem to give a nice boost compared to NiMH.

Just wondering if anyone else used them at all? Seem to be popular for cheaper RTR cars (like FTX etc.). I've found them good when size or weight of  a full NiMH pack is an issue.

 

 

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Carson has a pack for the SW-01 chassis that is made up of 2 x 18650, but that chassis only uses a 370 motor. Not an expert on this, but I think one problem I think with Li-Ion are their C ratings may not be enough for high powered motors. LG HG2, for example, have a 20A rating, probably good enough for little more than a silver can, while a 3000mah lipo pack has a 90A (30C x 3ah) rating. 

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15 hours ago, alvinlwh said:

Carson has a pack for the SW-01 chassis that is made up of 2 x 18650, but that chassis only uses a 370 motor. Not an expert on this, but I think one problem I think with Li-Ion are their C ratings may not be enough for high powered motors. LG HG2, for example, have a 20A rating, probably good enough for little more than a silver can, while a 3000mah lipo pack has a 90A (30C x 3ah) rating. 

That's a good point, but what's the C rating of an NiMH? I know that compared to a LiPO they are not quite there, but compared to NiMH they seem to give more punch - but that may be due to the weight reduction more than the power? 

To be honest I only use Torque Tuned motors, so no massive speed, power or discharges. The main use of the Li-Ions are for the QD and MF01x cars where NiMH Sub C cells wouldn't fit, but I have tried it in the GF01 heavy dump and will compare vs a freshly charged NiMH.

They are now approaching sub C capacity, which for the weight is amazing - but very few people seem to use them.

 

 

 

 

 

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10 minutes ago, Nikko85 said:

That's a good point, but what's the C rating of an NiMH? I know that compared to a LiPO they are not quite there, but compared to NiMH they seem to give more punch - but that may be due to the weight reduction more than the power? 

To be honest I only use Torque Tuned motors, so no massive speed, power or discharges. The main use of the Li-Ions are for the QD and MF01x cars where NiMH Sub C cells wouldn't fit, but I have tried it in the GF01 heavy dump and will compare vs a freshly charged NiMH.

They are now approaching sub C capacity, which for the weight is amazing - but very few people seem to use them.

Someone actually asked this question before and I looked it up, the C for NiMHs is typically 2 - 3C but with good ones, can do 5 - 10C. This is just some general numbers I found on the Web, which probably do varies depending on other factors, AAA will have less Cs than D cells? 

I have quite a few of them for my vapes and did consider building battery packs out of them at one point. However I was advised against it as it require some fancy welder, not the standard hot soldering iron, to do safely. 

There are videos of 18650s made into battery packs on YouTube, so there definitely is an interest in using them this way. 

Here is a test between the two. 

 

 

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I did a 18650 conversion on a TT02 and it works red out really well and much safer for those that don’t have the discipline for lipo.I think I did a post a year ago ish. 

 

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On 8/14/2022 at 4:51 PM, Nikko85 said:

Does anyone use Li-Ion batteries in their cars?

I've got a couple of cars running 3000 mAh 2s 18650 Li-Ions, which seem to give a nice boost compared to NiMH.

Just wondering if anyone else used them at all? Seem to be popular for cheaper RTR cars (like FTX etc.). I've found them good when size or weight of  a full NiMH pack is an issue.

 

 

I have been using Li-ion (titan power brand) for a while now (over two years) and I must say Im pretty happy with them.

MY POST ON THE MATTER

The experience so far has been great, better kick than NiMH but less than a medium C Lipo (they advertise as constant 36C equivalent), but none of the problems. If you are looking for bashing and dont have a need for pure performance then they might be a good option for you.  

I use the 2S 6000mah Nunchuck (airsoft batteries... eye roll) type, i just tape the two sticks together to have a brick the size of a standard nimh pack (been thinking about a 3D box), but they also have a 2S 3000mah in brick format. 

They also sell 3S equivalent batteries but have never tested one (size might be an issue here)

They are expensive, but I pay gladly for ease of mind, storing the batteries charged for instant use (They can retain their charge for months or years without problems or security issues), and general careless use like if they were NiMh.... 

 

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Thanks all.

I do have an issue dome help woild be great with plese. I am running a 2s Li Ion in a 1060. I was using the LIPO jumper setting, but after a min or two the car (GF01 on torque tuned) slows right down, as if triggering the half power warning. But when I test the battery it's reading 7.8 volts. When I put the jumper to NiMH it really goes.

Any idea what is going on? I would rather keep on Lipo so I have the voltage cut off, but for some reason it's getting triggered far too early.

Any ideas why? I may swap out the 1060 in case it's faulty.. 

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1 hour ago, Nikko85 said:

Any ideas why?

Not an expert on this, but I think the amp demand is over what the battery can supply. For example, on my vape device, if I set it to, say 40W, it will show low batt on 40%, but if I set it to 25W, it will only trigger at 20%. It is just unable to supply enough for demand, even when the V is high enough. 

Sometimes, if I force it, it can still power at 40%, but the indicator will show a rapid drop to empty and recover quickly after, therefore your reading of relatively high V. Unless you have a real-time read out, you will not know for sure. 

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1 hour ago, alvinlwh said:

Not an expert on this, but I think the amp demand is over what the battery can supply. For example, on my vape device, if I set it to, say 40W, it will show low batt on 40%, but if I set it to 25W, it will only trigger at 20%. It is just unable to supply enough for demand, even when the V is high enough. 

Sometimes, if I force it, it can still power at 40%, but the indicator will show a rapid drop to empty and recover quickly after, therefore your reading of relatively high V. Unless you have a real-time read out, you will not know for sure. 

That sounds about right, but with the li ion it's snappier than the NiMH, so shpuld have a higher C rating?

Although yes, voltage over load might do it, but it's strange.

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56 minutes ago, Nikko85 said:

That sounds about right, but with the li ion it's snappier than the NiMH, so shpuld have a higher C rating?

Although yes, voltage over load might do it, but it's strange.

IIRC, Li-Ion are not rated in C but A but I could be wrong. Anyway, the one that I have are rated at say 25 - 35A. Let's call it 30A, and 2Ah capacity. That means it is a 15C battery. Really nothing much compared to a RC lipo. 

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14 hours ago, alvinlwh said:

IIRC, Li-Ion are not rated in C but A but I could be wrong. Anyway, the one that I have are rated at say 25 - 35A. Let's call it 30A, and 2Ah capacity. That means it is a 15C battery. Really nothing much compared to a RC lipo. 

No you are correct but its still a lot more punchy than the NiMH so it's surprising that the low voltage is being triggered. I have had this issue running AA batteries through an ESC but thought something more punch than sub C NiMH would be fine.

Voltage drop over load could be it, but I'm not pushing the batteries too hard on a low geared GF01.

Edit: just tried with another battery, ESC and car, the same happened. Super fast for a minute, then slow again. Moving to the NiMH jumper and super fast.

So there is more than enough power to get the car going well, but must be dropping voltage in a way a LIPO wouldn't to trigger the warning.

May have to get a LIPO alarm perhaps. Oh well.

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3 hours ago, Nikko85 said:

No you are correct but its still a lot more punchy than the NiMH so it's surprising that the low voltage is being triggered. I have had this issue running AA batteries through an ESC but thought something more punch than sub C NiMH would be fine.

Voltage drop over load could be it, but I'm not pushing the batteries too hard on a low geared GF01.

Edit: just tried with another battery, ESC and car, the same happened. Super fast for a minute, then slow again. Moving to the NiMH jumper and super fast.

So there is more than enough power to get the car going well, but must be dropping voltage in a way a LIPO wouldn't to trigger the warning.

May have to get a LIPO alarm perhaps. Oh well. 

NiMHs, IIRC are around 3 - 5C, very good ones can be up to 10C but I don't that those are commonly available. And AA are only 1C?

There are a few ways to monitor voltage sag (I think that is the technical term?), one is to use a radio set with telemetry. Another method that may work, although I had not tried it with mine is to use an ISDT ESC70 with real time (not sure how fast or sensitive) feedback on the phone. 

That ESC is extremely feature rich but be warned, I had not have good luck with mine with half of what I bought (2 out of 4) being or going bad. Reviews on the Web seems to be the same. If you are to get one, make sure you buy from a easily refundable source. 

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Thanks for the reply. The cars with 390 motors and the 2030 brushless are all fine, it's just the 540s. Probably what happens is under the most extreme load the voltage drops, then goes back again, but the ESC enters panic mode! 

I've got a few options, one would be simply going back to the 7.2 pack for the GF01 and a slightly hotter motor, and a 4.8 Volt pack and hotter motor for the MF01x. The MF01x needs a smaller than stick pack battery.

A LIPO alarm could work, but to be honest I'd rather something that a) has an auto cut off and b) I can't forget.

I'd rather not spend too much on a new esc but thanks for that. I do have a spare TBLE04s, which has a cut off that might be more forgiving!

 

 

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Annoyingly when I tried the 4 cell 4.8 Volt pack the same thing happens on NiMH mode, although there seems to be some confusion in the literature if the HW1060 can take 4 or 5 cells minimum - but in reality 4 cells is too low for anything other than a very high turn motor.

I have tried a TBLE04S on high voltage (6.2) cut off to see what happens. Hopefully that will allow a window of use, and I am trying some 3300 mAh 18650s too, which seems to be working better.

The 18659 been brilliant in my Ezrun brushless ESC set to 3.0 volts per cell on 2030 motors, so I think it's just voltage drop over load, triggering a setting that is designed to handle the the power LiPOs can produce.

Worse case scenario is I have a 20T limit ESC for a Mardave/Kamtec, designed for 4 cells, so will go back to the NiMH pack on a lower turn motor, and keep the Li-Ions as spares.

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2 hours ago, Nikko85 said:

Annoyingly when I tried the 4 cell 4.8 Volt pack the same thing happens on NiMH mode, although there seems to be some confusion in the literature if the HW1060 can take 4 or 5 cells minimum - but in reality 4 cells is too low for anything other than a very high turn motor.

The 1060 (and 1625) will not take 4S NIMH. I had tried. However a Mtroniks one will. 

 

 

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3 hours ago, alvinlwh said:

The 1060 (and 1625) will not take 4S NIMH. I had tried. However a Mtroniks one will. 

 

 

You are spot on. The HW1060 literature says 5-9 cell andthen also 6-9 cell at different times (confusingly) but not at all 4 cell.

Mtronix does work well - although the brake function of mine is annoying, being the first third of the trigger travel in reverse for brake and the rest for reverse,- not the usual double tap I am used to. 

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1 hour ago, Nikko85 said:

Mtronix does work well - although the brake function of mine is annoying, being the first third of the trigger travel in reverse for brake and the rest for reverse,- not the usual double tap I am used to. 

This behaviour is not normal as I got a second one off a fellow member and it works with proper brake and delayed reverse (still not double tap). So did a few other rebranded ones. However when I returned mine to Mtroniks, they said all is fine (mine slams straight into reverse with no brakes). 🤷

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1 hour ago, alvinlwh said:

This behaviour is not normal as I got a second one off a fellow member and it works with proper brake and delayed reverse (still not double tap). So did a few other rebranded ones. However when I returned mine to Mtroniks, they said all is fine (mine slams straight into reverse with no brakes). 🤷

Mine seems to have this as a feature.

It is fine, but jarring when you are used to a double tap!

https://www.mtroniks.net/prod/car-speed-controls/Viper-Oval.htm

 

 

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