Hobbyking 6S BMS

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dirttorpedo
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Hobbyking 6S BMS

Post by dirttorpedo » Jan 28, 2018 12:16 am

Anyone have any experience with these? I've been charging 6s 10ah multistars to 25.2 with an HLG meanwell for months now. A few weeks ago I picked up a couple BMS boards. The discharge rate is a bit low for my needs so I only wired the JSTs, that way I can attach them only when I need to balance charge. Based on experiments with an old pack that never stayed in line, this works pretty well. The problem I have is that when I wire the main charge/discharge leads per the diagram at the bottom of this page:
https://hobbyking.com/media/file/845847 ... 138X47.pdf
the voltage on cell 6 shoots way through the roof almost instantly. I can see why. In the pdf the main + is wired to cell 6. This does not seem right to me.

So far it appears I can use these to balance anyway, with the boards at the JSTs and the charger plugged into the mains. I'm just curious how this thing is actually supposed to work when wired like it's shown in the diagram.





;
The Commuter: 2006 GT Kustom Kruiser- 16s LiFePo4 (25ah), generic Chinese motor, Grin 48v 35A
The Trail Bike: 1999 GT XCR-3000- 20s Calibike li-ion (15ah), H3540, Grin 72v 40A

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Re: Hobbyking 6S BMS

Post by amberwolf » Jan 28, 2018 12:32 am

dirttorpedo wrote:
Jan 28, 2018 12:16 am
The problem I have is that when I wire the main charge/discharge leads per the diagram at the bottom of this page:
https://hobbyking.com/media/file/845847 ... 138X47.pdf
the voltage on cell 6 shoots way through the roof almost instantly. I can see why. In the pdf the main + is wired to cell 6. This does not seem right to me.
That looks like a perfectly normal way to wire the cells to me. B+ is the main lead of a 6s pack that the 6s BMS is monitoring. The top (most positive) cell of that pack would also be internaly wired so it's + end is the B+ as well. (and the most negative end is the B-)

So if your cell's voltage changes when you wire it up that way, then either your balance cable set is miswired at the BMS or pack, or something else is wrong internal to the pack (or the BMS).

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Re: Hobbyking 6S BMS

Post by fechter » Jan 28, 2018 1:48 am

Double check your charger voltage. If it's running high it could cause that.

Also, if the other cells are not fully charged then the charger should be going into CC mode until they come up. If one cell is weaker or more charged than the others, it may reach HVC sooner and disable charge. Normally this causes it to cycle on/off as the balancing function bleeds down the high cell while it's off.

All this sounds pretty normal. It might improve if the pack gets more balanced.
"One test is worth a thousand opinions"

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Re: Hobbyking 6S BMS

Post by motomech » Jan 28, 2018 6:31 am

It seems to me that you are defeating the purpose of bulk charging by "breaking the string" to balance. My 2S/2P main pack of 4)MultiStar 6S/10 Ah is buried and I never disconnect them and although I ck. the cells most of the time I charge, they never need balancing.
20 Ah is big enough of a pack that there is no need to go for max top charge(above 4.10V) and to go below 3.70V. If you adhere to the 80% DOD rule, don't go disconnecting the string, you shouldn't have to balance more than once in a Blue moon. Providing your bricks aren't already hurt.
I would recommend you dump that balancer and go w/ this Battery Medic;
https://www.aliexpress.com/item/150W-3- ... 17404.html
There are clones(even HK sells them)and they are junk. Only the genuine BM';s w/ the lite bulbs are worth while.
Yes, they are passive discharge and are slow. But the point is to get the procedure down pat and get to the point where you don't have to balance. Then the speed doesn't matter.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
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https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by dirttorpedo » Jan 30, 2018 4:00 pm

Thanks guys. Two of my three bikes are "in the shop" right now so I won't be charging any lipo for a bit but I appreciate the help and tips.

I know I'm not technically bulk charging but I find my method works for me. I basically disconnect my discharge leads and connect the charge leads. This takes about 2 minutes and allows me to charge 6-9 6s 10ah packs in 2-3 hours. My charger was about half the cost of something with the same power at a higher voltage. It has worked great with no issues. I usually run lipo at 4.1 per cell but with the 4.35v max on the multistars I feel good about charging to 4.2. I run 18s 2 or 3p. I find that if I use 14ah at 2p and 21ah at 3p the cells are all at 3.8 at the end of the ride. I've been running this way since summer, 2-5 times a week, and have only now had to balance anything.
The Commuter: 2006 GT Kustom Kruiser- 16s LiFePo4 (25ah), generic Chinese motor, Grin 48v 35A
The Trail Bike: 1999 GT XCR-3000- 20s Calibike li-ion (15ah), H3540, Grin 72v 40A

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Re: Hobbyking 6S BMS

Post by motomech » Jan 30, 2018 4:42 pm

Yeah, since the HLG series only go up to 57 or so Volts, a bulk charger for your system gets complicated or expensive or both.
I still think you should get at least one Battery Medic that I linked. That's a great price and frankly, I don't see that the HK BMS is doing that much for you and the BM is easier to use. Since you are using a HLG CC/CV, you don't need the over-Current or over-Voltage protection and even if it was attached to the pack, the LVC is too low to be useful(What do you use for a LVC?). So basicly, it's just a checker and passive dis-charger.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by dirttorpedo » Jan 30, 2018 7:53 pm

Absolutely Motomech. I plan on getting at least three. I've got a couple from HK but they show slightly different voltages. I have one that checks out as dead on with my calibrated multi-meter. They also get so warm when I do even a little discharge with them that the screens fade out. I really appreciate the suggestion.
For LVC I plug in the little voltage alarms from HK set to 3.8 and set the LVC on my controller to 63v, about 3.5 per cell. It's a little lower than I want the cells to go but I figure it saves me from premature cut off due to sag under load. So far it's working nice. Like I said if I run about 7ah for each set of 3 packs I get back home at right about storage voltage. Usually I'm looking at 3.83s and 3.84s on all cells when I get home.
The Commuter: 2006 GT Kustom Kruiser- 16s LiFePo4 (25ah), generic Chinese motor, Grin 48v 35A
The Trail Bike: 1999 GT XCR-3000- 20s Calibike li-ion (15ah), H3540, Grin 72v 40A

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Re: Hobbyking 6S BMS

Post by motomech » Jan 31, 2018 7:19 pm

There has been three different Battery Medics;
1)The black ones that HK sells that are complete junk. The screen goes black as they over-heat and the values can only be set in .10 increments. HK should pull them from their line-up.
2)Then there are the blue ones that don't over-heat and the adjustments come in .05 steps.
3)And finally, the blue ones that come w/ the lite bulb dis-charger accessory. They fine tune @ .01 values. I tried the use the high discharge feature and wasn't very successful, but I have read of others here that have had it work well.
It's a good feeling to get a LiPoly system fine tuned, I've been using "bricks" for over 6 years and it still amazes me the amount of power that can had in such a small package. But there has been bumps along the way The first 2 years I fried two balance chargers, not junk either, A Thunder and a Hyperion and although there was no prem. damage, I've blackened my fingers a few times :roll:
I think the keys for getting my system as close to "plug and play" as possible have been staying at 14S and below, so I can use the Mean Well HLG's w/out "breaking the string" and the introduction of the MultiStar LiPoly a couple of years ago. I have this crazy idea in my head that LiPoly sort of has a memory and doesn't like to be disturbed :roll:
What the MultiStar did for me was make large bricks(10Ah and above)avail., so I could get the pack capacity I wanted and stay w/ 2P. I've never had any luck combining balance leads and prefer using a BM on each tap.
But the MultiStar has brought on some trade-offs. While it is lighter and smaller for a given capacity, it lacks the "punch" of say, my next fav. LiPoly, the Turnigy 25C. I still use the Turnigy where I have 6S bricks. But on the other hand, the MUltiStar is less volatile and I doubt it would catch on fire even if it was greatly abused. So, I.M.O., the MultiStar needs a fairly large pack to stiffen it up.
As for the HLG, well, you have one so you know how great they are. But you probably know all this other stuff too :wink:
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by amberwolf » Feb 01, 2018 2:06 am

I've been pondering, in the back of my head, and I guess these BMS units would work for things like my powerdrill pack (though now I'd need a 3s version instead of 6s, since the crappy HF drill burned out, so now I"m using an old lower-voltage Makita).
https://endless-sphere.com/forums/viewt ... 2#p1354572
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Re: Hobbyking 6S BMS

Post by dirttorpedo » Feb 01, 2018 9:21 pm

Moto, I've only been at this a year so any insights a vet like you and amberwolf have to offer are much appreciated. Eventually I plan on getting a true bulk set up, but for now what I have is super versatile. I still experiment with different pack configurations. Being able to charge 1 or 2 packs or as many as 9 has an appeal to me. Eventually when my commuter battery dies I'll settle on a 12s charger for that. On my dirt bikes I'll probably end up 18s or 24s or maybe somewhere in between.

Amber, I love that idea. I've been thinking a lot about using old packs to run my tools. So far I haven't even tried it because I'm not sure if the current would be to much for them.
The Commuter: 2006 GT Kustom Kruiser- 16s LiFePo4 (25ah), generic Chinese motor, Grin 48v 35A
The Trail Bike: 1999 GT XCR-3000- 20s Calibike li-ion (15ah), H3540, Grin 72v 40A

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Re: Hobbyking 6S BMS

Post by amberwolf » Feb 02, 2018 1:07 am

The battery doesn't push current, the tool pulls it, so the tool won't get any more current than it would with teh original battery.

Except: If the original battery had a lot of voltage sag, and the new one doesn't, then there may be more current flow (and total power usage, and heat) because of the higher voltage at the same resistance causing more current to be drawn from the battery.

That's why I'm using only 3s on my Makita, since it used to be a NiMH 14.4v. I figure a couple volts of sag on that (was unusably worn out when I got it, so no idea what sag it had when new) means the 12.3v I charge the 3s RC LiPo to should work out fine.

I used the same thing on the old Ryobi string trimmer, which had been a 12v 7Ah SLA unit, and it also ran fine *except* that it had so much more runtime on the RC LiPo that it didn't get the cooldown time it needed anymore, and eventually destroyed it's motor mount (plastic) and the motor. (it had no ventilation on the motor area, which with the SLA not lasting more than a very short time (less than half an hour when new, probably only a few minutes later on), was fine. Just not with long runtimes).

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Re: Hobbyking 6S BMS

Post by motomech » Feb 02, 2018 11:24 pm

dirttorpedo wrote:
Feb 01, 2018 9:21 pm
Moto, I've only been at this a year so any insights a vet like you and amberwolf have to offer are much appreciated. Eventually I plan on getting a true bulk set up, but for now what I have is super versatile. I still experiment with different pack configurations. Being able to charge 1 or 2 packs or as many as 9 has an appeal to me. Eventually when my commuter battery dies I'll settle on a 12s charger for that. On my dirt bikes I'll probably end up 18s or 24s or maybe somewhere in between.

Amber, I love that idea. I've been thinking a lot about using old packs to run my tools. So far I haven't even tried it because I'm not sure if the current would be to much for them.
I'm not aware of any 12S balance chargers. The Hyperion 14S and the Thunder 12S and 14S have not proven to be reliable and have been pulled from the market. Maybe 2 Mean Wells in series, but I have not looked into that because I'm happy with 14S charged by my HLG-320-54A, which adjusts up to 57 Volts.
Although I haven't repurposed "old" LiPoly bricks, I did end up with some 3S/3000mAh from some Aux. bottle battery experiments(I ended up using 3S/4000mAh bricks). I now use those 3000mAh pieces to power my headlight, heated grips and heated jacket.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by amberwolf » Feb 03, 2018 2:42 am

Something else to consider is that typical ebike controllers seem to be setup for LVC for 10s (36v), 13s (48v), 14s (52v), but not 12s (44v).

So unless yours has a programmable LVC, it's either going to cut off early, or not cut off soon enough, for 12s.

I could be wrong about that, but that's the types of packs I recall controllers being setup for from various threads on ES.

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Re: Hobbyking 6S BMS

Post by motomech » Feb 03, 2018 8:48 am

Actually, the 12S/48 V controller is the best match for LiPoly. For the 48V controllers I have, the fixed LVC is either 41V or 42 Volts, which works out to 3.50 V/cell. But in practice, at that low discharge level, one or two cells gets out frt.(going lower) and w/ sag, the actual avg. cell level is usually around 3.65 Volts at LVC.
When I used a 36 Volt controller w/ a LVC of 31 V, I matched up w/ 9S, which ended up w/ the same cell levels at LVC as above.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by TimJ » Feb 11, 2018 10:25 pm

Hi Motomech,

I've noticed several of your posts on the topic of bulk charging lipos using the battery medics as a cell monitor and balancer. I was wondering if you feel it's important to have one attached to every pack throughout the charge. As an alternative, I was thinking it would serve the same purpose if all cells are checked before and after each charge and I could do a balance if there are differences between cells of a pack that exceed a couple 1/100s of a volt. You have commented that you rarely have to do balance charging at all, so is there a benefit to have the BM's on all packs all the time? It seems like it would be pretty quick and easy to move a single BM between each pack's balance connector as a check before starting the charging, and again afterwards. I thought it would probably be a good idea at the beginning of the battery life to balance charge each pack individually a couple times before going to bulk charging, but if the cells in all packs are maintaining the balance, how important is it to have several separate BM's? I am planing to use a 14s2p configuration (like a few others I have seen recently), and with the Multistars, this means ( 2*4s+1*6s ) * 2, which would require 6 separate BM's. I don't plan on pushing the batteries to their limit in terms of upper or lower limits nor on the discharge rate (probably 1-3C most of the time), so I am thinking this will be fairly gentle on the batteries. Am I missing something about the operation of the battery medics?

Your opinion is much appreciated!

Thanks,
-Tim

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Re: Hobbyking 6S BMS

Post by amberwolf » Feb 11, 2018 11:30 pm

If you have well-balanced packs, that have no cells that might have different internal resistance than others, then you could just check before and after.

But if you have packs that have varied cells in them, you'd probably want to monitor them during charging to ensure none go too high especially during the high-current phase of charging.


With my EIG cells I check balance every so often (usually every few months or less often) at various states of charge and during charging's high-current phase, and don't typically find any problems.

WIth the RC LiPo I would often check it during charge and sometimes during discharge, and at first didnt' find much of a problem, but over time it grew unbalanced enough to start worrying about / balancing it (with a BM) about every other charge cycle. Nowadays I don't use that pack except for testing stuff out; it's puffed up and degraded significantly, but I used it hard before that happened. :)

With a small commercial 18650 pack I let the BMS do it's thing; it seems to get unbalanced every cycle even if I don't push it hard. I don't use it much except for testing, either, because most of my stuff needs a lot more than it can handle.

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Re: Hobbyking 6S BMS

Post by TimJ » Feb 12, 2018 8:50 pm

Thanks for the feedback, Amberwolf.

One other thing I thought about and was wondering if it would help keep cells balanced is to parallel individual cells together across the strings using the balance cables and just leave them that way all the time. With the right connections, the cells in both strings could be balanced simultaneously using the battery medics. A possible negative (?): If there is a bad cell in one of the packs, it would pull down the parallel cell in the other string, so this could cause a problem I suppose. But if you monitor the cells on a very regular basis and are easy on the packs, I would think it could be rather helpful for long term cell health. I'd love to hear others' comments.

I had seen some discussion on one or two threads in ES about doing parallel then series connections vs. series then parallel, but I didn't really see an argument that I found convincing either way. I did a little looking at lunch time today and came across the following from batteryuniversity.com:

http://batteryuniversity.com/learn/arti ... igurations
With Li-ion, the parallel strings are always made first; the completed parallel units are then placed in series.
I think this probably refers to how the cells are configured in commercial packs, but if it's appropriate at the cell level, it seems like it would probably be a good idea at the pack level also.

There is a lot of good info in the batteryuniversity articles. I have seen a couple links to them in posts but I didn't check to see if they appear in some of the stickies or other reference materials in ES. If not it would be good to include some links.

-Tim

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Re: Hobbyking 6S BMS

Post by motomech » Feb 12, 2018 11:03 pm

I use a two-stage charge process. After the ride, at some point I will take them up to storage charge- 3.90V-3.95V /cell. Then check 'em. As I start to think about out going out, I will start the top charge while I ck. the tires and air shock. After 10 or 15 minutes, I'm usually between 4.00V and 4.10V, which is enough w/ my 12S/20Ah, 2S/2P pack. I never leave any of the BM's on while charging, since I'm not going to sit there watch for a stay cell. And you can't leave them on all the time because they drain the brick.
I like to keep the cells within 3 hundredths, but at extreme top charges(4.10V and above)sometimes they will stray a bit and I'll go at 5 hundredths. They tend to come back together during the dis-charge cycle.
I thought it would probably be a good idea at the beginning of the battery life to balance charge each pack individually a couple times before going to bulk charging,...
I used to cycle them a couple of times on my little RC balance charger, but the Multistar's are so steady out of the box, I don't bother anymore.
but if the cells in all packs are maintaining the balance, how important is it to have several separate BM's?
There are times. Say I just top charged and for some reason, I didn't go. So now I need to bring all 4 bricks down the storage level and since the BM's have the discharge rate akin to a melting glacier, I'll clip a BM on each brick and let them come down overnite. Or when I do something stupid like I did the other nite. The exact same scenaro, top charged and didn't go out. So I thought I would connect my monster h.lite, leave it on for a couple of hr.s and see what that did. Bad idea! It took all the energy from the first brick in my 2S/2P config. and not only was one brick way below the others, but the cells in that brick were all over the place! In that case, I set the BM values to match the single lowest cell(like 3.75V in this case) and they were still working when I got up in the morning.
I am planing to use a 14s2p configuration (like a few others I have seen recently), and with the Multistars, this means ( 2*4s+1*6s ) * 2, which would require 6 separate BM's.
Well, I would say 6. but look at it this way, you are already saving BIG $$$ by using LiPoly and if you follow my link on which BM's to buy, you won't waste money on the black BM's like I did.
One other thing I thought about and was wondering if it would help keep cells balanced is to parallel individual cells together across the strings using the balance cables and just leave them that way all the time.
No, you don't want to do that for several reasons, but suffice to say, you want all the speed the BM's will muster when you want to pull the whole pack down and that means a BM on ea. brick. And you are right about a low cell pulling down it's mate. Don't do it.
I had seen some discussion on one or two threads in ES about doing parallel then series connections vs. series then parallel, but I didn't really see an argument that I found convincing either way. I did a little looking at lunch time today and came across the following from batteryuniversity.com:
I series two bricks first, then parallel the 2 pr.s, 2 less Y-adapters needed. It's not like you are going to melt wires w/ the Multistars. In the same vein, although I make my own, you can use the skinny 14 Ga. "off the shelf" Y-adapters w/these low-powered systems.
There is a lot of good info in the batteryuniversity articles. I have seen a couple links to them in posts but I didn't check to see if they appear in some of the stickies or other reference materials in ES. If not it would be good to include some links.
Battery University is universally scorned here by the "experts". Unless you want to be derided, I wouldn''t mention that name again :)
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: Hobbyking 6S BMS

Post by TimJ » Feb 13, 2018 9:47 am

Thanks for the detailed reply, motomech. This is very helpful.

-Tim

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Re: Hobbyking 6S BMS

Post by maydaverave » Feb 13, 2018 1:14 pm

Can several of these bms be ran parallel? I've never had a lipo pack, seems like to much of a pain to me. But a 20 ah pack made from 5ah packs could put out 40amps and be bulked charged easily?
e-bikekit 50v 9.2ah cellman pack

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Re: Hobbyking 6S BMS

Post by TimJ » Feb 15, 2018 8:12 am

Yes to all. Note that the battery medics (BM's) referenced in this thread are not the same as a bms (battery management system), so careful not to confuse the two when reading. More often than not, when someone says bms/BMS, they are referring to the management sysstem. But the battery medics can be installed on all packs, either in parallel and/or series. 20 Ah capacity can comfortably put out 40-50A continuous (this is only a 2-2.5C discharge) and at least double that for short bursts. I (ad many others) am using Multistars, rated at 10C, but many other lipos are rated for 20C and even higher. The Multistars are known for being very stable and are quite reasonably priced, and many people routinely do bulk charging without issues. There is some initial setup and making sure that cells are balanced, but bulk charging is a viable option for these batteries. I just bought a 14s2p configuration of 10Ah packs (around 1kWh capacity) for about $350 from hobbyking.com. 16Ah and 20Ah packs are also available.

-Tim

dirttorpedo
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Re: Hobbyking 6S BMS

Post by dirttorpedo » Feb 16, 2018 4:16 pm

motomech wrote:
Feb 12, 2018 11:03 pm
I like to keep the cells within 3 hundredths
This sounds really cool to me. I was under the impression that they should be kept within 1 hundredth. It was several months of use before I saw a variance of .02. Lately all of mine are within 1 hundredth after a ride (3.8 and 3.81 or 3.79 and 3.8 ) but vary 2 or 3 hundredths after charging. I probably wouldn't have to balance for months at a time if I let them ride at a .03 difference. This works well for you Moto?
The Commuter: 2006 GT Kustom Kruiser- 16s LiFePo4 (25ah), generic Chinese motor, Grin 48v 35A
The Trail Bike: 1999 GT XCR-3000- 20s Calibike li-ion (15ah), H3540, Grin 72v 40A

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