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2023: BMS Systems Changing & Improving

Steve_S

Emperor Of Solar
Joined
Oct 29, 2019
Messages
8,476
Location
N.E. Ontario, Canada
Good Day Folks,

Well here we are in April 2023 and things are changing fast post "Covidus Interruptus" and good things are happening ! Prices stabilizing and even going down in some sectors (not food sadly), new bigger, better & more capable products including BMS'.

After converting all of my battery packs in my Bank from Chargery BMS to JKBMS things have been working very well and without issues and their 2A Active Balancing works a treat. Sadly JK shot self in foot with lowering their Quality and not following through on issues and essentially going dark when they should be communicating with people. So I have been keeping a "Lazy Eye" on BMS development and this spring everything is changing for the better.

NOTE: I have NOT tested any of these BMS below yet. I am presently leaning towards the TDT BMS and depending on what my contacts "on the ground" come up with I hope to be testing soon.

BMS' that are worthy of attention for good reason.
PACE BMS is used by Jakiper & Others for their prebuilt battery packs and these have shown good communication & compatibility with Victron etc.
They have the RS232/485 & CanBus (works out of box by default) as well as being linkable together. They have limited 8S Versions but are mostly 16S for 48V battery systems. PACE also produces HVDC BMS's for >48V but that crosses into other areas.
I did locate PACE 16S/100A with all the goodies for $130 USD on Global Sources.
More info on PACE here: http://bms.paceic.com/en/bms/

EVE BMS ! Yes BMS' by EVE Battery Tech co...
EVE has been producing cells of course but also complete battery systems like the popular 48V/100AH Server Racks and a lot more. They use their own BMS of course and they are now also becoming publicly available. They are also quite feature/function filled.
- General Info is only now coming available as they start offering them.
More "basic" info available here(16S/48V/200A): https://www.alibaba.com/product-detail/EVE-EBS48-BMS-48V-Lifepo4-Battery_1600753983743.html

TDT BMS another Growing & Expanding company that produces similar BMS' to PACE but their own flavour.
This is not a new company but has moved slowly & cautiously up to their current offerings.
Tradie reviews show these to be quite good with good compatibility as well, at very good price points as well.
Passive Balancing with option for Active Balancing module up to 5A.
MANY options for displays & interface boards etc... (not that common, this is a bonus)
REASONABLY PRICED TOO !
More Info HERE: https://sztdttech.en.alibaba.com/productgrouplist-903398691/Energy_storage_BMS.html
NOTE: Lots of browsing in the above link.

I am certain there are several others with Advanced Smart BMS' that have PC/Mac Software, Proper Compatible Comms via CANbus and RS with a respectable display (not power hog), and the plug-in interface boards etc...

PLEASE NOTE to Readers / Responders.
Feel free to add BMS Companies that have come out with new Smart & Advanced BMS' and if you actually have them and are using/testing them...
PLEASE do NOT start bashing or posting troubles with your existing gear UNLESS it is directly related to a "Brand" posted in this thread.
* Some of these BMS are used in Commercial Server-Rack/Telecom rack batteries which may be "locked" by the manufacturer, thereby not allowing full config access. The "standalone" BMS' should be "unlocked" providing full access to config options etc. VERIFY THIS with your vendor/supplier Before spending a penny !!!

Lastly, I may once again do a full write up with results etc and more if/when I get to that point. I will NOT however write any more manuals or docs for anyone but may put up a tips & trix sheet for our membership here. For me, it is shaping up to be an extremely busy summer, 2 Arrays, another complete solar system and quite possibly an all-season greenhouse (if that happens, that's yet another array) so much todo and a full job jar.

Have a Great Day Everyone - Spring has Sprung !! well springing anyways ;-)
 
missing seplos here
Quite correct, my bad for missing it, kinda obvious eh... ;-)

Link to SEPLOS BMS: https://www.seplos.com/battery-management-system
While these have also attracted a LOT of attention, there are certain compatibility issues (Victron CANbus) as discussed by YT'ers as well as issues with Paralleling different "Versions" of the BMS'. AGAIN this is all sourced from assorted reviews on YT and what has been stated here on the forums. What is currently Corrent ? I don't know as they do a lot of updates & attempt to keep up.

Critical KEY FEATURE OF ANY BMS that shoudl be Highlighted:
IF the BMS has Updateable Firmware which can be flashed for updates, MANY do not have this ability, including JK (they say it does but there is no way to do it) although it is possible someone somewhere figured it out, if so Please DO TELL !
 
Quite correct, my bad for missing it, kinda obvious eh... ;-)

Link to SEPLOS BMS: https://www.seplos.com/battery-management-system
While these have also attracted a LOT of attention, there are certain compatibility issues (Victron CANbus) as discussed by YT'ers as well as issues with Paralleling different "Versions" of the BMS'. AGAIN this is all sourced from assorted reviews on YT and what has been stated here on the forums. What is currently Corrent ? I don't know as they do a lot of updates & attempt to keep up.

Critical KEY FEATURE OF ANY BMS that shoudl be Highlighted:
IF the BMS has Updateable Firmware which can be flashed for updates, MANY do not have this ability, including JK (they say it does but there is no way to do it) although it is possible someone somewhere figured it out, if so Please DO TELL !
so, lets see if i can answer some ..

firmware is upgradable, through pc software.
interoperability :
currently there are 3 versions around, 2 of which are older, one is current.
10c - canbus inverter comms only - older
10d - rs485 inverter comms only - older

10e - newest and current both rs485 and canbus.
can communicate directly with both 10c and 10d, however, not both at the same time.

10c also has a bluetooth option and app

the difference in hardware is also the reason 2 older versions cant communicate to each other


do not have victron, so can't speak on the inoperability, i do have Sunsynks , and these will communicate seamless with other subbrands ( deye and sol-ark)


weakpoint of this bms is their passive balancer.
so if choosing this bms, make one does a proper top balance, and one uses matched cells of good quality.
optionally one can add a neey or other active balancer

the 10e version also supports 64 linked batteries, and come in a few sizes, like 100a ,150a and 200a.
Seplos specificly does not support or mixing different sizes in 1 communication stack


made a few correction changing 10c to 10e
 
Last edited:
so, lets see if i can answer some ..

firmware is upgradable, through pc software.
interoperability :
currently there are 3 versions around, 2 of which are older, one is current.
10c - canbus inverter comms only - older
10d - rs485 inverter comms only - older

10c - newest and current both rs485 and canbus.
can communicate directly with both 10c and 10d, however, not both at the same time.

10c also has a bluetooth option and app

the difference in hardware is also the reason 2 older versions cant communicate to each other


do not have victron, so can't speak on the inoperability, i do have Sunsynks , and these will communicate seamless with other subbrands ( deye and sol-ark)


weakpoint of this bms is their passive balancer.
so if choosing this bms, make one does a proper top balance, and one uses matched cells of good quality.
optionally one can add a neey or other active balancer

the 10c version also supports 64 linked batteries, and come in a few sizes, like 100a ,150a and 200a.
Seplos specificly does not support or mixing different sizes in 1 communication stack
Thanks, this is quite helpful.

I noted that the TDT while similar to PACE & even SEPLOS for the most part, has optional Active Balancing Modules up to 5A.
I don't know if PACE or TDT have flash upgradeable firmware.
Being that it is Sunday and presently 01:27AM in Shengen I am sure I will get some answers beginning in the Wee Hours here. Have to say, the more I look at the TDT offerings and the options the more it twigs me.

One reason for the TWIG... I am currently 24V so 8S is needed but I built my system so I could easily flip the packs to 48V requiring a 16S. TDT does have models which can operate as 8S or 16S, so that fits with how I setup my project. Many things are changing here now and the switch to 48V for 240VAC service is looking more & more likely to happen this summer or fall.
 
Thanks, this is quite helpful.

I noted that the TDT while similar to PACE & even SEPLOS for the most part, has optional Active Balancing Modules up to 5A.
I don't know if PACE or TDT have flash upgradeable firmware.
Being that it is Sunday and presently 01:27AM in Shengen I am sure I will get some answers beginning in the Wee Hours here. Have to say, the more I look at the TDT offerings and the options the more it twigs me.

One reason for the TWIG... I am currently 24V so 8S is needed but I built my system so I could easily flip the packs to 48V requiring a 16S. TDT does have models which can operate as 8S or 16S, so that fits with how I setup my project. Many things are changing here now and the switch to 48V for 240VAC service is looking more & more likely to happen this summer or fall.
sure does sound interesting, however, since im using seplos mason enclosures, and have too many to replace front plate and bms, i'll stick with what i have for now

btw i heard jk also has a server rack battery size bms..
also should have active balancing
 
also, i forgot to add..

seplos actually has a pretty smart way of balancing.
yes they do have a 200mv burn of balancing, but their software microcycles the cells at the top end ( which is user definable) which helps in conjunction with the passive balancing and charge amp throttling to 10 amps to work just a bit better.
this does however only work in conjuction with closed loop communication with your inverter
i rarely see my cells out of wack , but this does require a regular full changing so the microcycling can take place
 
Just got some word, so a bit of an update:
EVE BMS are now indeed becoming available to the public BUT they are quite expensive at this time. They are not in the General Sales Stream yet but expected by mid-summer.

PACE-BMS are limitedly available to the public (used by Jaikper & others) but are apparently having some technical issues, that was not clarified. 2 of my contacts have paused using them for now but they would not tell me why, one is now evaluating the TDT-BMS.

TDT-BMS I contacted a supplier for more info and hit the wall with one of those reps who can't read & respond to points.... Oivey !!! In process of having someone "on-the-ground" get me the required info BUT after a couple of days of researching, TDT is looking better & better.
NB: Starting a thread requesting Info/Feedback on TDT.

The Thread:
 
Last edited:
Just got some word, so a bit of an update:
EVE BMS are now indeed becoming available to the public BUT they are quite expensive at this time. They are not in the General Sales Stream yet but expected by mid-summer.

PACE-BMS are limitedly available to the public (used by Jaikper & others) but are apparently having some technical issues, that was not clarified. 2 of my contacts have paused using them for now but they would not tell me why, one is now evaluating the TDT-BMS.

TDT-BMS I contacted a supplier for more info and hit the wall with one of those reps who can't read & respond to points.... Oivey !!! In process of having someone "on-the-ground" get me the required info BUT after a couple of days of researching, TDT is looking better & better.
NB: Starting a thread requesting Info/Feedback on TDT.
still really interesting...
hopefully the choices for server rack batteries will expand over the next months..
i heard JBD is also working on one to be released soon
 
There are no features on that list that my ten year old REC BMS doesn’t have.

The main direction i’ve seen over the last ten years with BMS development is to get a cheap ebike BMS and market it as suitable for a larger stationary power system, then adding active balancing to bandaid the inability of the BMS to limit charging while balancing. The number of failures resulting in destroyed packs has been astonishing, yet people still insist on getting the “cheap” option.

You can keep trying your luck on the cheapies, hopefully the next one you get is what you are looking for.

I wouldn’t buy any of the BMS’ you have mentioned, over the lifespan of my system i doubt i could afford them.
 
There are no features on that list that my ten year old REC BMS doesn’t have.

The main direction i’ve seen over the last ten years with BMS development is to get a cheap ebike BMS and market it as suitable for a larger stationary power system, then adding active balancing to bandaid the inability of the BMS to limit charging while balancing. The number of failures resulting in destroyed packs has been astonishing, yet people still insist on getting the “cheap” option.

You can keep trying your luck on the cheapies, hopefully the next one you get is what you are looking for.

I wouldn’t buy any of the BMS’ you have mentioned, over the lifespan of my system i doubt i could afford them.
Quickly worked the numbers. REC-Q16 full kit with relay, precharge & PC-Software and cables = 950 USD ea. I presently have 6 packs with more to come.

REC is not being looked at IN THIS THREAD they are a known good premium product.

The number of failures resulting in destroyed packs has been astonishing, yet people still insist on getting the “cheap” option.
REALLY ? Where do you get that, I am here everyday and read posts and 90% of issues resulting "in damage" is user to gear failure...
Hell in my Thrash Tests I have done the "Abuse" to extremes and there wasn't any Cell Issues when I popped a BMS or two. Those Cells are still all going without issues. "Astonishing" is FUD not FACT...

No Further Sidetrips off-topic...
Thanks.
 
REALLY ? Where do you get that, I am here everyday and read posts and 90% of issues resulting "in damage" is user to gear failure...
Hell in my Thrash Tests I have done the "Abuse" to extremes and there wasn't any Cell Issues when I popped a BMS or two. Those Cells are still all going without issues. "Astonishing" is FUD not FACT...

Maybe he's thinking about Daly BMS?
 
I am in need of 3 100+amp BMS's ... like as soon as today (or in the next few weeks) that will be usable for 8s and then will allow me to switch to 16s in the near future (system upgrade from 24 to 48v).

@Steve_S are you saying at this point in time the JK BMS (such as the B2A24S20P) is still the BMS of choice, or should I be looking elsewhere and/or waiting on your results from the list above ?
 
This is side tripping which I don't want in this thread.
JKBMS is OKAY but over the past 6 months they have dropped to "possibly dubious" as their quality control dropped & support vanished.
I am presently running on all JK but had to replace one that Poofed that decided the MOS temp was always above 122C.
Now looking at the alternatives and waiting on info...

FYI: TDT Company has 2 STRIKES already as sales reps are playing the idiot game and not answering questions posed directly... 3rd Strike & Rule of 3 is Expended and they are out... I ave some feet on the ground there checking into some things for me...
 
Quickly worked the numbers. REC-Q16 full kit with relay, precharge & PC-Software and cables = 950 USD ea. I presently have 6 packs with more to come.

REC is not being looked at IN THIS THREAD they are a known good premium product.


REALLY ? Where do you get that, I am here everyday and read posts and 90% of issues resulting "in damage" is user to gear failure...
Hell in my Thrash Tests I have done the "Abuse" to extremes and there wasn't any Cell Issues when I popped a BMS or two. Those Cells are still all going without issues. "Astonishing" is FUD not FACT...

No Further Sidetrips off-topic...
Thanks.
You only need one REC BMS for 6 packs.

I’ll bow out now as you seem to know everything, looks like it’s been working well for you so far ?
 
I am in need of 3 100+amp BMS's ... like as soon as today (or in the next few weeks) that will be usable for 8s and then will allow me to switch to 16s in the near future (system upgrade from 24 to 48v).

@Steve_S are you saying at this point in time the JK BMS (such as the B2A24S20P) is still the BMS of choice, or should I be looking elsewhere and/or waiting on your results from the list above ?
I'm sticking with my JK's.
I only know of one person who has had problems. And I don't believe that the BMS was the cause.
 
The EVE Bms looking exciting with a downside of its 60ma active balancing, not a problem for perfectly always in balance cells. Pairing it with a higer capacity balancer raises its cost astronomically but its ability to communicate with most inverters is a huge plus
 
Can add another one after seeing it on Andy's Garage. https://www.gobelpower.com/gobel-rn...85-rs232-screen-for-lifepo4-battery_p104.html

$360 shipped to USA :rolleyes:.. Still don't know much and seems Andy will review it in more details in next video. But already seems to have lot more capability then the JK BMS.

I thought the same

There are actually two models that could be worth looking into
Gobel RN150 BMS (150A)
Gobel PC200 BMS (200A)

There seem to be zero documentation though on either..
 
I'm still having trouble justifying that price.. it should have at least had an active balancer built-in and thorough documentation.
 
Good Day Folks,

Well here we are in April 2023 and things are changing fast post "Covidus Interruptus" and good things are happening ! Prices stabilizing and even going down in some sectors (not food sadly), new bigger, better & more capable products including BMS'.

After converting all of my battery packs in my Bank from Chargery BMS to JKBMS things have been working very well and without issues and their 2A Active Balancing works a treat. Sadly JK shot self in foot with lowering their Quality and not following through on issues and essentially going dark when they should be communicating with people. So I have been keeping a "Lazy Eye" on BMS development and this spring everything is changing for the better.

NOTE: I have NOT tested any of these BMS below yet. I am presently leaning towards the TDT BMS and depending on what my contacts "on the ground" come up with I hope to be testing soon.

BMS' that are worthy of attention for good reason.
PACE BMS is used by Jakiper & Others for their prebuilt battery packs and these have shown good communication & compatibility with Victron etc.
They have the RS232/485 & CanBus (works out of box by default) as well as being linkable together. They have limited 8S Versions but are mostly 16S for 48V battery systems. PACE also produces HVDC BMS's for >48V but that crosses into other areas.
I did locate PACE 16S/100A with all the goodies for $130 USD on Global Sources.
More info on PACE here: http://bms.paceic.com/en/bms/

EVE BMS ! Yes BMS' by EVE Battery Tech co...
EVE has been producing cells of course but also complete battery systems like the popular 48V/100AH Server Racks and a lot more. They use their own BMS of course and they are now also becoming publicly available. They are also quite feature/function filled.
- General Info is only now coming available as they start offering them.
More "basic" info available here(16S/48V/200A): https://www.alibaba.com/product-detail/EVE-EBS48-BMS-48V-Lifepo4-Battery_1600753983743.html

TDT BMS another Growing & Expanding company that produces similar BMS' to PACE but their own flavour.
This is not a new company but has moved slowly & cautiously up to their current offerings.
Tradie reviews show these to be quite good with good compatibility as well, at very good price points as well.
Passive Balancing with option for Active Balancing module up to 5A.
MANY options for displays & interface boards etc... (not that common, this is a bonus)
REASONABLY PRICED TOO !
More Info HERE: https://sztdttech.en.alibaba.com/productgrouplist-903398691/Energy_storage_BMS.html
NOTE: Lots of browsing in the above link.

I am certain there are several others with Advanced Smart BMS' that have PC/Mac Software, Proper Compatible Comms via CANbus and RS with a respectable display (not power hog), and the plug-in interface boards etc...

PLEASE NOTE to Readers / Responders.
Feel free to add BMS Companies that have come out with new Smart & Advanced BMS' and if you actually have them and are using/testing them...
PLEASE do NOT start bashing or posting troubles with your existing gear UNLESS it is directly related to a "Brand" posted in this thread.
* Some of these BMS are used in Commercial Server-Rack/Telecom rack batteries which may be "locked" by the manufacturer, thereby not allowing full config access. The "standalone" BMS' should be "unlocked" providing full access to config options etc. VERIFY THIS with your vendor/supplier Before spending a penny !!!

Lastly, I may once again do a full write up with results etc and more if/when I get to that point. I will NOT however write any more manuals or docs for anyone but may put up a tips & trix sheet for our membership here. For me, it is shaping up to be an extremely busy summer, 2 Arrays, another complete solar system and quite possibly an all-season greenhouse (if that happens, that's yet another array) so much todo and a full job jar.

Have a Great Day Everyone - Spring has Sprung !! well springing anyways ;-)
Be careful with the TDT BMS, i have purchased about 20 units for them and have done extensive testing. When doing a multipack installation, the slave packs start displaying inaccurate SOC after a couple of days; the remaining capacity indicator of the slave battery packs lowers gradually automatically redefining the full capacity rating of the battery; eventually a battery you configured as 280 amps becomes a 200 amp battery; the master battery however continues to function and display correct readings. So you cumilitive soc being displayed by the inverter and in effect guiding your inverter settings become completely innaccurate. How do we know that the SOC readings on the slave batteries are incorrect and a result of poor reading by the shunt; well these batteries voltages are identical to the master battery 1, indicating the actual state of charge of the slaves is similar to the master in reality; and we have done testing where we have pushed these slave packs with innacurate SOC down below 0 confirming that the automatically recalibrated FULL CAPACITY rating of our pack was innacurate and that all our slave batteries were in actuallity at the same state as the master. The manufacturer cannot answer any questions in regards to this, they tell us to discharge to 0 and fully recharge, this gives 0 results, after a couple of days the same thing repeats. Also the cell voltage reading of the BMS on apps is more innacurate in comparison to other brands . This product has tons of potential, but it has not been tested well by the manufacturer and has serious issues with calibration .
 
Good Day Folks,

Well here we are in April 2023 and things are changing fast post "Covidus Interruptus" and good things are happening ! Prices stabilizing and even going down in some sectors (not food sadly), new bigger, better & more capable products including BMS'.

After converting all of my battery packs in my Bank from Chargery BMS to JKBMS things have been working very well and without issues and their 2A Active Balancing works a treat. Sadly JK shot self in foot with lowering their Quality and not following through on issues and essentially going dark when they should be communicating with people. So I have been keeping a "Lazy Eye" on BMS development and this spring everything is changing for the better.

NOTE: I have NOT tested any of these BMS below yet. I am presently leaning towards the TDT BMS and depending on what my contacts "on the ground" come up with I hope to be testing soon.

BMS' that are worthy of attention for good reason.
PACE BMS is used by Jakiper & Others for their prebuilt battery packs and these have shown good communication & compatibility with Victron etc.
They have the RS232/485 & CanBus (works out of box by default) as well as being linkable together. They have limited 8S Versions but are mostly 16S for 48V battery systems. PACE also produces HVDC BMS's for >48V but that crosses into other areas.
I did locate PACE 16S/100A with all the goodies for $130 USD on Global Sources.
More info on PACE here: http://bms.paceic.com/en/bms/

EVE BMS ! Yes BMS' by EVE Battery Tech co...
EVE has been producing cells of course but also complete battery systems like the popular 48V/100AH Server Racks and a lot more. They use their own BMS of course and they are now also becoming publicly available. They are also quite feature/function filled.
- General Info is only now coming available as they start offering them.
More "basic" info available here(16S/48V/200A): https://www.alibaba.com/product-detail/EVE-EBS48-BMS-48V-Lifepo4-Battery_1600753983743.html

TDT BMS another Growing & Expanding company that produces similar BMS' to PACE but their own flavour.
This is not a new company but has moved slowly & cautiously up to their current offerings.
Tradie reviews show these to be quite good with good compatibility as well, at very good price points as well.
Passive Balancing with option for Active Balancing module up to 5A.
MANY options for displays & interface boards etc... (not that common, this is a bonus)
REASONABLY PRICED TOO !
More Info HERE: https://sztdttech.en.alibaba.com/productgrouplist-903398691/Energy_storage_BMS.html
NOTE: Lots of browsing in the above link.

I am certain there are several others with Advanced Smart BMS' that have PC/Mac Software, Proper Compatible Comms via CANbus and RS with a respectable display (not power hog), and the plug-in interface boards etc...

PLEASE NOTE to Readers / Responders.
Feel free to add BMS Companies that have come out with new Smart & Advanced BMS' and if you actually have them and are using/testing them...
PLEASE do NOT start bashing or posting troubles with your existing gear UNLESS it is directly related to a "Brand" posted in this thread.
* Some of these BMS are used in Commercial Server-Rack/Telecom rack batteries which may be "locked" by the manufacturer, thereby not allowing full config access. The "standalone" BMS' should be "unlocked" providing full access to config options etc. VERIFY THIS with your vendor/supplier Before spending a penny !!!

Lastly, I may once again do a full write up with results etc and more if/when I get to that point. I will NOT however write any more manuals or docs for anyone but may put up a tips & trix sheet for our membership here. For me, it is shaping up to be an extremely busy summer, 2 Arrays, another complete solar system and quite possibly an all-season greenhouse (if that happens, that's yet another array) so much todo and a full job jar.

Have a Great Day Everyone - Spring has Sprung !! well springing anyways ;-)
Sorry,
Because we have received many inquiries about the product,
We have also been adjusting and upgrading our products in the past six months
I have been focusing on upgrading product performance,
Improve the overall after-sales rate of the product. Improve customer experience.
Finally, the complete inverter communication issue was debugged this month,
There is also the issue of parallel current limiting,
We finally solved it
 

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