looking for recommendations for BMS upgrade

Joined
May 13, 2014
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Location
Montreal, Canada
Hi everyone!

I snagged a 48V 12Ah Li-ion battery on eBay today:

https://www.ebay.com/itm/48V-12Ah-Li-ion-Battery-with-Aluminum-Case-500W/122752553886?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

The seller said that it has a bad BMS, which really isn't that big of a problem, however... (sigh), I started checking the specs and I found this:

"Please do not use the battery on the 1000W motor because of the BMS limit. If your motor is 1000w, please choose our 48V15AH or 20AH battery!"

Since I'm planning to use this on a 9.5 kw motor, I'm really going to need a better BMS and I was wondering of anyone had a recommendations for me. This is my first Li-Ion pack, I've been using SLA's until now, so I'm a total newbie with this type of battery setup. I have decent coding/programming skills, so I can use an Arduino or Raspberry Pi if necessary.

Also, since the battery is new, is it possible to buy some similar cells and increase the packs AH's, (I'm planning to disassemble the pack to custom fit it into my project

Thanks!

zog
 
Dependent on your controller you should be matching your battery to that. If your planning to run 9kw using 48v your going to need around 180 amps. Your battery and wires are going to heat up like a toaster. As for your idea of stripping the pack down that’s a great idea. Using identical cells is the only way to go and you need to be sure of the state off every cell. I assume the pack was new so shouldn’t be an issue. But once again the controller dictates how much power you feed to the motor, not the battery. The same as a throttle dictates how much gas you give to a car, not the gas tank, but it’s always a good idea to carry extra gas in the tank. Have a hard look at the controller you are using and build your pack around that, not the motor.
 
Just going to toss in some inexpert/novice comments. I am still learning about BMS circuits myself, and hope to learn more in any ensuing discussion here. If I'm wrong, be glad to know it.

In my opinion, that warning you see about using their bigger batteries for higher wattage should (a) be heeded and (b) is not really because of the BMS. I think the cells in the battery aren't capable of powering a 1000W motor under acceleration. They will sag enough when we open the throttle on a big motor to trip any BMS put on it.

You should open it up and see how many you have in parallel. I was looking at some of those $200 bottle batteries on ebay, and saw one rated at 12AH that claimed to be 6P. Not that I trust those ebay descriptions, but six 2AH cells in parallel? Gotta be puny cells. And maybe you can see what kind of cells were used, if the markings/labels can be traced.

Meanwhile I was wondering how I would tell my BMS design to limit current. Seems to me I need a shunt circuit. I don't see any shunt wires on the cheap BMS in my hoverboard batteries. I bought some cheap BMS boards to replace the former and they also have no shunts. I bet they they just open the tap and let the cells limit current. They all use two MOSFET's, and one by itself is enough to handle at least 30A if given a heat sink. I'm thinking that aside from a shunt circuit, BMS current ratings are derived from the quality of the heat sink.
 
If you're planning to match this pack to a 9.5 kW motor, a new BMS is the least of your worries. At 9.5 kW, this battery would be drained in about 4 minutes, assuming it didn't burst into flames first, and I'd put the cycle life in the single digits.

Maybe you should give some details on your current setup (motor, controller, SLA number and capacities, etc.) to get more informed advice about how to go about switching to lithium.
 
Right, 9.5kW is a lot of motor. That battery won't come even close before it burns up. Maybe 10 of them in parallel would work. You want the BMS to trip before the batteries overheat or get damaged, so BMS choice depends on what cells and the configuration.
 
Hi everyone,

Thanks for the tips.

cycborg said:
If you're planning to match this pack to a 9.5 kW motor, a new BMS is the least of your worries. At 9.5 kW, this battery would be drained in about 4 minutes, assuming it didn't burst into flames first, and I'd put the cycle life in the single digits.

Maybe you should give some details on your current setup (motor, controller, SLA number and capacities, etc.) to get more informed advice about how to go about switching to lithium.

Good point! Here's what I'm working with, (and I will say "NO!" in advanced to the questions regarding if I am under the care of a mental health expert! ;) ).

So the motor is an Imperial Electric P66LR006 industrial permanent magnet motor, rated at 36v that I have been running at 48v on my, (heavily), modified Razor Dirt Quad:

Imperial_2.jpg


This is the motor next to a 36v 1000w Unite. The motor weighs in at 54 lbs and has an internal fan, so over heating at the higher voltage isn't a problem.

As I said, I had it on a modded dirt quad:

the_beast_5.jpg


the_beast_6.jpg


I had to rebuild the rear swing arm to fit the motor. I called the build "The Beast" because of the motor. The problem with it was a combination of a huge amount of torque and the center of gravity being to high, giving it some nasty handling, even on straight roads. I was using a Kelly KDZ48200 for the controller and 4 x 12v 18ah SLA's for the battery pack.

I was looking for a go kart frame to put the motor on when I found this mini bike chopper at a flea market:

spawn_1.jpg


It originally had a 5 hp gas motor on it that the seller wanted $125.00 for. I told him that I didn't want the motor and he let me have the frame for $40.00

My initial plan was just to swap everything from the quad, but one of the 12v 18ah SLA's went bad and while perusing eBay for some new SLA's, I came across the LI-Ion pack that I will be receiving on Monday.

I was just realized that the motor is 9.5 hp, not kw, ( :roll: What did the Scarecrow say, "If I only had a brain!")! I had no problems running it on the previous battery pack, (the battery that went bad was due to my not storing it properly before doing a 1500 mile trip from Montreal to Florida).
 
Well, it looks like I was a good boy this year, because Santa, (i.e. USPS), brought me my toys early! Here's what I got:

battery_1.jpg


battery_2.jpg


Here,s the top of the battery:

battery_top.jpg


The BMS:

bms_1.jpg

bms_2.jpg


There appears to be a short in the BMS, (as the seller stated in the auction):

bms_3a.jpg

bms_4.jpg

bms_5.jpg


To my surprise, this battery appears to be made of 3.2v LIFEPO4 cells instead of Li_Ion's that the seller advertised. I'm not complaing, I just was expecting round cells, (Sigh, backto the drawing board on my plans! ;) ).

battery_4.jpg

battery_5.jpg


There is writing on the side that reads:

battery_6.jpg


HY11F14
104111E28
HPPN7070260 - 12AH

OK, now that I know what I'm working with, what would be my best choice for a replacement BMS? Also, is it possible to add more cells to increase the ah's? I think that I already know the answer to this question, but I'll ask it anyway, if I can add batteries to increase the ah's, can I use round cells, or do they have to be flat cells?

Thanks!

zog
 
So it looks like a 13s, 12Ahr LiFePO4 pack. A quick search on eBay didn't come up with any 13s boards, but there are plenty of 16s versions, which should work if the unused channels are tied together at the positive end.

example: https://www.ebay.com/itm/48V-30A-LiFePo4-Battery-BMS-LFP-PCM-SMT-System-16S-16x-3-2V-eBike-Battery-16x-3V/112488768436?hash=item1a30da63b4:g:6ewAAOSwaGFZcLww

BesTech Power will likely have a 13s somewhere.

You may be able to fix the blown BMS if just the FET is bad.

That pack will be able to run about 20A. Not nearly enough for "the Beast".

Yes, you can add more cells in parallel to increase capacity. Shape doesn't matter, but chemistry does. A123 cells are the same chemistry, but generally good at much higher discharge rates than the generic Chinese LiFePO4 cells.
 
fechter said:
So it looks like a 13s, 12Ahr LiFePO4 pack. A quick search on eBay didn't come up with any 13s boards, but there are plenty of 16s versions, which should work if the unused channels are tied together at the positive end.

example: https://www.ebay.com/itm/48V-30A-LiFePo4-Battery-BMS-LFP-PCM-SMT-System-16S-16x-3-2V-eBike-Battery-16x-3V/112488768436?hash=item1a30da63b4:g:6ewAAOSwaGFZcLww

BesTech Power will likely have a 13s somewhere.

You may be able to fix the blown BMS if just the FET is bad.

That pack will be able to run about 20A. Not nearly enough for "the Beast".

Yes, you can add more cells in parallel to increase capacity. Shape doesn't matter, but chemistry does. A123 cells are the same chemistry, but generally good at much higher discharge rates than the generic Chinese LiFePO4 cells.

Thanks fechter!

LOL, it looks like I will have to use this pack for another project and get the SLA's I was originally planning! :( Still, it was a good find and since I always have another project going on....
 
BTW, here is the spec sheet on the Imperial Electric P66LR006:

Imperial_motor.jpg


Maybe I'm wrong about it and the batteries will work? (He says hopefully!)

Hmm, I just realized that it's 3 hp?!?! Not sure why I thought that it was 9.5. (I've done so many project that they seem to blur sometimes! :lol: )
 
It looks like it's rated as a 100A motor.

If the controller you're using with it is also rated at 100A motor output, (at least 100A battery input), then the battery has to be rated to output at least that amount of current (and with cheap batteries, I'd get one rated for twice that so voltage sag wouldn't be so horrible, and cycle life would be longer).

At 48V, then depending on voltage drop under load, it's around 4800W or higher.

Now, whether you'll actually be using that much power depends on how it's geared to reach the road, and how fast you're going and whetehr there are hills, headwinds, etc.

But on accelration from a stop, it's likely to take the full power it's capable of if you use full throttle, for at least part of that acceleration up to cruising speed.


My old CrazyBike2, using a small powerchair motor (overvolted, I forget how many watts I got out of it now, but I was using a 4QD controller that was once able to supply something like 2-3kw just before it blew the FETs, when the chain jammed and folded sprockets and destroyed the rear wheel just before it ripped the chain apart) used the same SLA types you've got on the 4-wheeler, the 18Ah (some were 20Ah). These didnt' last very long, either in range or in lifetime, if I pushed them hard. But if I'd used a really cheap Li pack (like you have in this thread) for the bike, it'd've nuked it quick unless I babied it.

Using the larger (group 22? I forget) power chair SLA I didn't get as much voltage sag, but pushing them hard they still didn't live very long.


I've gone thru a lot of different kinds of batteries now, and the only ones so far that haven't let me down are a pack of A123 LiFePO4 20Ah pouch cells from EM3EV, and various packs of EIG NMC 20Ah pouch cells in different configurations. I'm still using these, and they were already well-used when I originally got them from other people.

The next best were some RC LiPo packs in 2p 10Ah configuration, but eventually their relatively short cycle life caught up with them, too. (and I never really trusted them to not burst unexpectedly into flames, even though they still havent).


For the current demands your system may have, you could use 18650 cells, too, but you'd want a whole bunch of them in parallel to keep the per-cell load minimal, and that makes a big pack. If you used 50p, to keep it down to only 2A per cell (for however long 100A is drawn), then for a 14s "52v" pack that's 700 cells. (and a lot of interconnections). A 13s "48v" pack is only 50 cells less.

(there's cells that can sustain higher currents, but they have less capacity, so if you need more range you still have to have more cells)


If the motor isn't ever getting hot then I suspect you're not using anywhere near the max current / power for more than a moment or two, and so you don't need 100A continuous--but if the controller can take that much at all, the battery still has to support that for however long and often it asks for it.

If you have a wattmeter, you should test the system out (on the 4wheeler would be fine, if it still exists) and see what the system draws under various conditions.

THen you can extrapolate what you'd get with the bike with that system, given it's different purpose/speeds/riding conditions/gearing/wheelsize/etc.

Then you can figure out what battery you actually need to get the speed, acceleration, range, and battery lifespan you're after.
 
3hp continuous is a big motor. For short bursts, it can do way more than that, probably closer to the 9.5hp. Supplying 100A is the challenge. Lead works but horribly short range and cycle life. The A123 prismatic pouches would be a huge improvement and relatively safe. The other option would be Lipo. More prone to catching fire, but a lot of power in a small package. Personally, I would pick Lipo over lead-acid.
 
Yes; even with a steel box around them as "fire safe" they're still smaller and lighter. ;)

And more cycle life for the price, though still not as long as I'd like.
 
amberwolf said:
The next best were some RC LiPo packs in 2p 10Ah configuration, but eventually their relatively short cycle life caught up with them, too. (and I never really trusted them to not burst unexpectedly into flames, even though they still havent).

fechter said:
Personally, I would pick Lipo over lead-acid.

amberwolf said:
Yes; even with a steel box around them as "fire safe" they're still smaller and lighter. ;)

And more cycle life for the price, though still not as long as I'd like.

Thanks everyone. I've played with lipo's in the past,however, I live full time in a 36' motorhome these days and the thought of having lipo's in my highly flammable coach... :shock:

I guess the most practical thing to do is find a motor that will draw less power. Even more piratical would be to pop on a 5 hp gas motor and sell the chopper. I really don't wan't to sell a gas scooter, (I'm not a fanatic, I just like to breath the air!). I will have to see what my budget can handle.

I'm picking up a Razor E300 this week, so I'll either repair the BMS or buy a new one and use the battery in that. I'm kind of tired of SLA's, the weight alone is a big factor. I will save up and buy some decent Lifepo4's or maybe some batteries from a scraped e-vehicle, I've been noticing more and more of them showing up on eBay these days.

Thanks to everyone for their help and willingness to educate me. I'll be able to plan better in the future for a project like this
 
zogthegreat said:
I guess the most practical thing to do is find a motor that will draw less power.
And weighs less. ;)

But it's not just that the motor draws the power--it's that the controller provides it and limits it. AFAICS, you havent' said what controller you're using or what it's limits are.

If it has multiple shunt wires in it you can simply remove one or more of htem, reducing it's current limit by that proportion. (if it has four, removing one reduces it by 25% ).



I'm kind of tired of SLA's, the weight alone is a big factor.
FWIW, the motor probably weighs as much as the SLAs. If you're not using that motor's capabilities, changing to a motor closer down to the capabilities you'll actually use from it will reduce weight and power needs will reduce from that, too.


maybe some batteries from a scraped e-vehicle, I've been noticing more and more of them showing up on eBay these days.
There's a number of threads about those; spinningmagnets started an index of types and info, too.
 
fechter said:
So it looks like a 13s, 12Ahr LiFePO4 pack. A quick search on eBay didn't come up with any 13s boards, but there are plenty of 16s versions, which should work if the unused channels are tied together at the positive end.

example: https://www.ebay.com/itm/48V-30A-LiFePo4-Battery-BMS-LFP-PCM-SMT-System-16S-16x-3-2V-eBike-Battery-16x-3V/112488768436?hash=item1a30da63b4:g:6ewAAOSwaGFZcLww

BesTech Power will likely have a 13s somewhere.

I found these on the BesTech site:

http://www.bestechpower.com/416v13spcmbmspcbforlifepo4batterypack/PCB-D245.html

http://www.bestechpower.com/416v13spcmbmspcbforlifepo4batterypack/BMS-D205.html

https://www.ebay.com/itm/48V-30A-LiFePo4-Battery-BMS-LFP-PCM-SMT-System-16S-16x-3-2V-eBike-Battery-16x-3V/112488768436?hash=item1a30da63b4:g:6ewAAOSwaGFZcLww

I like the 16S one from eBay, I can always try to reuse it after these cells reach end of their life, (if I don't fry them first! :roll: ), and build a larger pack with it. However, since I'm a total noob to these, I will ask more experienced and knowledgeable people which board they would choose, (and why!)

fechter said:
You may be able to fix the blown BMS if just the FET is bad.

I took a second look at the board and I'm not sure if it can be repaired. You can't see it on the pic, but the circuit path on the board is missing about 1.5 mm of material and the board looks like it's burnt underneath it. Since I don't know what caused it to fry in the first place, I really don't want to risk the batteries when a new board is cheap.
 
I found another thread about this project tht says you've got a Kelly KDZ48200
http://kellycontroller.com/kdz4820024v-48v200aseriespm-p-951.html

whcih means that unless you change it in it's programming, it will allow 200A if the motor asks for it (which it can at startup from a stop, or in stall conditions, even as a 100A motor), for up to a minute. Continuous it'll allow 80A.

But it is programmable, if you have the stuff to do it (if not, ask Kelly about that)
 
BTW amberwolf, I just noticed that your from Phoenix. I lived in Mesa until I was 15, (my father was stationed at Williams AFB), and I'm heading back to AZ in May, (IMO, the east coast sucks and it seems that I'm allergic to everything on this side of the Continent!), although I'm planning to go somewhere between Prescott and Flagstaff, (I've lived in the north to long, I would melt in the valley! :lol: ).

Are there any laws about e-vehicles that I should know about before I head out there?

Thanks!
 
amberwolf said:
But it is programmable, if you have the stuff to do it (if not, ask Kelly about that)
Yeah, I was thinking about that and I checked the programming software and while it will allow you to adjust the voltage, it doesn't allow you to play with the amps. :(

kelly_step_1.PNG

kelly_step_2.PNG

kelly_step_3.PNG
kelly_step_4.PNG

kelly_step_5.PNG
 
At present, there's nothing specific to e-cars/motorcycles/etc. An e-version has the same rules/limits/etc as a ICE version.

For e-bikes, there is no power limit, just a speed limit of 20MPH, controlled by the operator. Other than that, it just has to meet the definition of a bicycle, which here in AZ is very simple.
28-101. Definitions

6. "Bicycle" means a device, including a racing wheelchair, that is propelled by human power and on which a person may ride and that has either:

(a) Two tandem wheels, either of which is more than sixteen inches in diameter.

(b) Three wheels in contact with the ground, any of which is more than sixteen inches in diameter.

https://www.azleg.gov/viewdocument/?docName=https://www.azleg.gov/ars/28/02516.htm
28-2516. Motorized electric or gas powered bicycles or tricycles; definition

A. Notwithstanding any other provision of this title:

1. A certificate of title is not required for a motorized electric or gas powered bicycle or tricycle.

2. Registration is not required for a motorized electric or gas powered bicycle or tricycle.

3. Vehicle license tax is not imposed on a motorized electric or gas powered bicycle or tricycle.

4. A motorized electric or gas powered bicycle or tricycle is exempt from the provisions of section 28-964 relating to required equipment on motorcycles and motor-driven cycles and from the provisions of title 49, chapter 3, article 5 relating to vehicle emissions inspections.

5. A driver license is not required to operate a motorized electric or gas powered bicycle or tricycle.

6. A motorized electric or gas powered bicycle or tricycle may use rights-of-way designated for the exclusive use of bicycles.

7. A motorized electric or gas powered bicycle or tricycle is not subject to chapter 9 of this title.

B. This section does not prohibit a local authority from adopting an ordinance that regulates or prohibits the operation of motorized electric or gas powered bicycles or tricycles, except that a local authority shall not adopt an ordinance that requires registration and licensing of motorized electric or gas powered bicycles or tricycles.

C. For the purposes of this section, "motorized electric or gas powered bicycle or tricycle" means a bicycle or tricycle that is equipped with a helper motor that has a maximum piston displacement of forty-eight cubic centimeters or less, that may also be self-propelled and that is operated at speeds of less than twenty miles per hour.

ARS title 28 has all the details.
https://www.azleg.gov/arsDetail/?title=28
Some sites taht list and interpret them
http://azbikelaw.org/arizona-bicycle-laws/
https://en.wikipedia.org/wiki/Electric_bicycle_laws#Arizona
 
zogthegreat said:
Yeah, I was thinking about that and I checked the programming software and while it will allow you to adjust the voltage, it doesn't allow you to play with the amps. :(
It does show a Max Motor Current, and a Max Battery current--are those not adjustable?

(if you don't have it connected to the controller, it might nto allow adjustment of things until it can talk to it).

If it's not directly adjustable, you could use it in "reverse mode", swapping the two wires from motor to controller so the mtoro still runs forward, and then enable the half-current option. That'd get you down to 40A continuous and 100A peak, at least. ;)




If you do come to AZ, you should pop down to Phoenix for a visit. The last week of April I'll be on a week's time off from work, so I'll be around the house almost all of the week, except for grocery trips and the like.

If you won't be here till after that, I'll be on another week off just about every other month (to be sure to use up my PTO so I don't lose it).
 
amberwolf said:
At present, there's nothing specific to e-cars/motorcycles/etc. An e-version has the same rules/limits/etc as a ICE version.

For e-bikes, there is no power limit, just a speed limit of 20MPH, controlled by the operator. Other than that, it just has to meet the definition of a bicycle, which here in AZ is very simple.
28-101. Definitions ....... http://azbikelaw.org/arizona-bicycle-laws/
https://en.wikipedia.org/wiki/Electric_bicycle_laws#Arizona

LOL, either your very active in the e-bike community, or you have had a chat or two with the sheriff's department! :wink: Or both!

amberwolf said:
It does show a Max Motor Current, and a Max Battery current--are those not adjustable?

(if you don't have it connected to the controller, it might nto allow adjustment of things until it can talk to it).

If it's not directly adjustable, you could use it in "reverse mode", swapping the two wires from motor to controller so the mtoro still runs forward, and then enable the half-current option. That'd get you down to 40A continuous and 100A peak, at least. ;)

Sorry, I haven't been sleeping very well or very much the last few days, brain no go at full capacity, (says the man playing with high voltage/amp toys! :shock: ). I'll try fiddling with the settings on the controller. The set up was recommended to my by a member on another build forum. He's a very creative builder, but he likes power and speed to the point that many of the forum members question his sanity at times! :wink: I've been playing with Razor scooters and SLA's for the most part, gradually building up my knowledge and skills based on reading what other people have done and asking questions as often as possible. This battery pack is my first foray into "real" hardware.

amberwolf said:
zogthegreat said:
If you do come to AZ, you should pop down to Phoenix for a visit. The last week of April I'll be on a week's time off from work, so I'll be around the house almost all of the week, except for grocery trips and the like.

If you won't be here till after that, I'll be on another week off just about every other month (to be sure to use up my PTO so I don't lose it).
[/quote]

My sister lives in North Phoenix, so I should be coming to the valley regularly, although perhaps not in August! 20 years of living up in Quebec has toughened me to the cold, (I laugh at my sister when she complains about the temperature "dropping into the 60's!), but I will have to get used to the heat again! Hopefully I will have something road worthy by then. I've been considering building a bamboo bike. Maybe I'll design something that incorporates a e-bike into the actual design. Or I could do a simple conversion on my Jamis mountain bike.
 
zogthegreat said:
LOL, either your very active in the e-bike community, or you have had a chat or two with the sheriff's department! :wink: Or both!
There isn't really a local community for ebikers, though I see them around now and then. I've tried to start one here on ES
https://endless-sphere.com/forums/viewtopic.php?f=25&t=71340
but there doesn't seem to be much interest.


I try to get together wiht ones I see but most are not interested in talking (same wiht most cyclists even when i was just a pedal type before electrics). I've met up with a few I found here on ES, a few times, but not often. Most are not in my area, and most also use ebikes / bicycles for recreation, not a lifestyle like I do (car-free).

I used to try to meet up with the FreakBikeNation group, but even though my bikes definitely qualify, they generally frown on anything with a motor on it of any kind, so I didn't really feel all that welcome, and haven't gone back to the meetups downtown in years. (the meetups also almost always happen on nights I have to work, which doens't help--I don't even know if they still do them). The FBN forum went away some time back, (they started a new one but all the stuff on the old one is gone, and so are most of the people; the forum software and appearance is also not really usable for me, so I don't go there either).


As for knowing the law, I find it's helpful to ensure what I'm going to do is legal to do before I do it, and also that knowing the law means LEOs are less likely to mess with me (and I can also educate them since many have no knowledge of bicycle law much less ebike law).

FWIW, it's kind of strange, but since creating and riding things that don't really look like bicycles (or much of anything else you'd usually see), I actually have less problems with anyone than I did when I was just riding pedal-only bikes, or even "normal" looking ebikes. There's some info on that (and the local laws) in the linked thread above, too.



Sorry, I haven't been sleeping very well or very much the last few days, brain no go at full capacity,
That's my normal state of life, so I understand perfectly. :/ I usually spend my first day off each week sleeping in and resting as much as I can, just so I can catch up and maybe accomplish some household tasks the other day off, before going back to work.



My sister lives in North Phoenix, so I should be coming to the valley regularly, although perhaps not in August! 20 years of living up in Quebec has toughened me to the cold, (I laugh at my sister when she complains about the temperature "dropping into the 60's!), but I will have to get used to the heat again!
I'm not sure it's possible to get used to the summer heat. :) I've been here more than 30 years (not counting a few more years as a kid when my parents were moving around), and I can only say I tolerate it, and less well each year as I get older. I prefer teh cold, because its a lot easier to bundle up to stay warm than to strip down past your skin to shed heat. ;)




Hopefully I will have something road worthy by then. I've been considering building a bamboo bike. Maybe I'll design something that incorporates a e-bike into the actual design. Or I could do a simple conversion on my Jamis mountain bike.
There's build threads here for Jamis bikes of various types if you poke around, that might help. Also bamboo builds. There were some bamboo ones on the old FBN too; dunno if there's any on the new one (but no motorized ones).
 
So, after 2 bleeping months, I finally received my new BMS:

BMS_1.jpg


I really don't recommend the seller that I got the BMS from, 2 months is somewhat excessive, IMO. I will list him in the for sale section so people know to avoid him.

So, now the question is how to hook it up to my battery. Do I connect the wires one for one, starting with the red one on from my old BMS? I seem to remember someone mentioning that I needed to hook the spare wires to the red wire, but I can't find the post.

Thanks!

zog
 
Yes, connect the balance wires in sequence starting at the negative end then tie the extra unused wires to the battery positive. Be very careful to keep the wires in correct order or you can blow things up. I always try to connect the main plug at a slight angle so the negative end makes contact first. Make the B+ connection last
 
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