Monitor and Charge 10s Pack

[bob_cbr]

Hello,

Been using my e-bike for 350km now (Build review be posted soon) and all was good until a full loss of power. It looks like the BMS went and it got me thinking, about my battery.

I've been using a cheap 10s BMS of ebay:

Now, for all I know, the battery could have a fault or the BMS could be a bust. The simple issue is my current setup does not provide me with enough information about the battery health.

My ebike has a LCD display with voltage readout of the whole pack, but I would like:
1. To monitor the 10s in real time. Every meter / Logger seems to be 1-8 cells max.
2. Balance charge a 10s pack with readouts. Is a icharger-1010b the only option on the market. OR
3. Use a better BMS with some kind of indication of its output.

Any experience from people would be great. For now, I'm running without BMS and charging to 41V and discharging to 35V. Getting a better multimeter too.

Regards,
Bob

 

[sonnetg]

You can probably try and connect two CellLogs to monitor 10S. I use iCharger 1010 for now, but there may other RC chargers available to balance charge more than 10S, but i haven't found any so far (always seems to be out of stock or unavailable).

You can also use a PCB BMS and add extra harnesses to hook up multiple Celllogs.

Another option would be to use Addapto Max-E or Mini-E controllers & BMS, but I suppose that would require a major upgrade to your existing electronics.

 

[bob_cbr]

Hi,
Thankyou for the info.

Do not know much about Addapto Max-E or Mini-E controllers & BMS, will do some google research about that tomorrow.

Using more than one logger is a good idea. I'll price that option up.

For my 3s lipo I used to use a small voltage read out board. It scrolled through each cell voltage and the pack voltage. They only cost a couple of pounds each. I could use a few of them to give me a real time readout of the cell voltage.

Just seems like there is a gap in the market for supporting larger battery packs. Charger / logger wise anyway.

I put my rubbish multimeter over the suspect bms mosfets and one of them gave a different ohms reading compared to the other three. Looks like that might be the issue.

Well the battery is charging now without bms, will stop it at 40v which will give me enough power to make it into work.

Still I need to make a decision on how I next balance the pack. New pcb bms (any brand recommendations) or 10s charger. £10 vs £150.

Regards,
Bob.

 

[motomech]

Hello,

Been using my e-bike for 350km now (Build review be posted soon) and all was good until a full loss of power. It looks like the BMS went and it got me thinking, about my battery.

I've been using a cheap 10s BMS of ebay:

Now, for all I know, the battery could have a fault or the BMS could be a bust. The simple issue is my current setup does not provide me with enough information about the battery health.

My ebike has a LCD display with voltage readout of the whole pack, but I would like:
1. To monitor the 10s in real time. Every meter / Logger seems to be 1-8 cells max.
2. Balance charge a 10s pack with readouts. Is a icharger-1010b the only option on the market. OR
3. Use a better BMS with some kind of indication of its output.

Any experience from people would be great. For now, I'm running without BMS and charging to 41V and discharging to 35V. Getting a better multimeter too.

Regards,
Bob

Are we talking LiPoly here??
If so, what is your configuration, ?S/?P, how many bricks of what capacity?
You could use the Icharger, but I.M.O., bulk charging and forgetting the BMS is the way to go on an ebike.
What is the LVC(low Voltage cut-off)of your controller?

View attachment 1
Bulk charging 5 Ah of 12S w/ Mean Well HLG and 2) Battery Medics



Bulk charging 20 Ah of 12S w/ Mean Well HLG and 4) Battery Medics

 

[Inwo]

Try a smart bms. Only about $50 with 10 cell display on computer or Android device.
I have a 14s model I'm using now. Should have some 12s tomorrow.
Will be changing one of them to 10s. I hope. As I have a 10s 200ah pack ready to go, less bms.
Since I found these I can't imagine going back to a simple bms.
A few threads about them here on es.

 

[bob_cbr]

I bought my Battery of this forum from the user tumich.
LG MG1 (config 10S4P/37V, 11,6Ah/400Wh)
Really good quality pack and just want to ensure it keeps that way.

My controller has a LVC of 30V but I would never take it below 32V loaded. TBH, not sure if I have ever seen much below 35V.
I try to charge to 41V, but sometimes let it fully charge so it balances. Only had it a couple of months.


Right... We have some really good options. Love option 2.

1. My super cheap solutions to a real-time readout of battery voltage would be:
http://www.ebay.co.uk/itm/RC-Lipo-B...hash=item3ac453a07e:m:md6n6fjcqhfTOJGZxs7q_gA
Couple of those should be able to monitor a 10S pack.

2. Smart BMS. Wow, This looks awesome. Nice call Inwo.
I first looked at:
https://bmsbattery.com/bmspcm/833-s...ttery_type-lithium_ion/107-cells_in_series-10
But the postage was like 80% the value of the product.
Total products £34.65
Total shipping £27.24
TOTAL £61.89

In the end, I found the same (Ish) on aliExpress with free shipping:
https://www.aliexpress.com/item/36V...lgo_pvid=2bcbe6fa-6572-4aca-ac6a-ba7d751e5502

An alternative would option put might be a bit pricey for me would be:
https://endless-sphere.com/forums/viewtopic.php?f=31&t=78552&hilit=smart+bms
https://www.energusps.com/shop/product/tiny-bms-s516-30a-16
Does look quality though!!!

3. icharger-1010b, which cost so much in the UK.


At the moment I am favoring the AliExpress Smart 10s BMS. Never ordered of there before, so will be interesting.
I really like the idea of bulk charging via a BMS, then letting it balance the pack. It just needs to output more data. Aka - Smart BMS.
oh and I might order solution 1, just for the fun of it.

Any other idea welcome,
Bob

 

[miuan]

You have a very good quality pack to start with. Do not spoil it with a cheap BMS that can fail without warning, nor with a monitoring device that draws power from selected cells and unbalances your pack by design.
You will be fine with a single cell log and just a brief check before charging. The battery should keep balance for years.

 

[petemarconi]

You have a very good quality pack to start with. Do not spoil it with a cheap BMS that can fail without warning, nor with a monitoring device that draws power from selected cells and unbalances your pack by design.
You will be fine with a single cell log and just a brief check before charging. The battery should keep balance for years.

+1

 

[dogman dan]

Your starting point for whatever, might be to add the plugs you need for monitoring, or at least checking anytime, with devices like a cellog.

For a 10s pack, add two 6 pin plugs to your bms wires. so a bunch of Y connections.

Nothing wrong with another bms, cheap or good, but you can watch what the bms is doing while it charges if you have the plugs for monitors.

 

[mark.curry3]

Just got the smart bms with the pictured accessories but zero instructions. Now I have a bunch of stuff and no Idea where to begin. Any idea where to get instructions on use/hookup?

 

[Inwo]

All about the same.

 

[mark.curry3]

But how does the communication Port work

 

[Inwo]

The small one is bt. Other is for sw.
Did they give you a link to sw and app?
I'm computer illiterate, plugged it in and it worked. Luckily.
Board will not power from USB. Disappointing.
I did not try powering from B- and B+ only. Connected to balance leads and B- to make it comunicate.

 

[Inwo]

http://www.lithiumbatterypcb.com/download-center

 

[Inwo]

If someone smokes a bms board, I ordered a few extra without accessories.
I can get you one quick in usa.
10s-15s boards only.
I'm using a different model for 15s-24s and yet another for 25s-32s.

 

[mark.curry3]

there did not send any download info. Thanks for letting me know it will not power with usb. I have not attached the leads yet(big battery and wanted to check this out before lugging it out of bike and opening). Is there a download link on the page referred to? looking for it

found it

 

[mark.curry3]

View attachment 1 OK Here is the new BMS--20s---with markings. I thought that b- was battery neg and P- was motor neg with c- charger neg and B+ charger pos but this diagram shows neg charge and discharge attaching to C- and no mention of P-. Any Idea what is right?

 

[kocetoMR]

Charge and discharge port are the seme.look board Housing ("P-" no needed)
If you need software and android app send PM

 

[mark.curry3]

thanks.. got android app but it gets stuck "initializing". I have the latest android version

 

[bob_cbr]

Well call me Lazy but I finally got around to fitting my Bluetooth BMS!!!!!
So here is the conclusion.

Quick recap:
Ran my Ebike with a cheap BMS which blew after 350Km.
Created this thread because I wanted a way to balance my cell and a way to monitor my battery voltages.
User: Inwo recommended a smart BMS with Bluetooth, which I ordered, but it then sat in a cupboard all this time. Until Yesterday.

Another user: Miuan said:

You have a very good quality pack to start with. Do not spoil it with a cheap BMS that can fail without warning, nor with a monitoring device that draws power from selected cells and unbalances your pack by design.You will be fine with a single cell log and just a brief check before charging. The battery should keep balance for years.

So being lazy, I ran the battery without BMS for that last 1200Km. Charging to ~41V. My commute is 12km, so that's around 100 bulk charges (ISH), that I have done one this battery without BMS.

Yesterday the kids went to bed early, so I got the soldering Iron out, the Smart BMS and rigged it up.
Plugged it into the laptop as I was very interested to see how balanced the cells were after 1200Km of riding and 100 cycles of bulk charging.
1. 3.846v
2. 3.846v
3. 3.838v
4. 3.847v
5. 3.847v
6. 3.846v
7. 3.847v
8. 3.848v
9. 3.849v
10. 3.850v

Amazing, just like Miuan said, the pack did indeed stay balanced without a BMS.
I do like my new smart BMS, cheers Inwo. It has only been on the battery since yesterday, so not used it in anger yet.

Any questions welcome.

 

[999zip999]

A battery with new high quality cells should stay in balance if used used and charged in it's limits. 4.15 to 3.6 - 3.5v. The lower you go the more possible problems.