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Recommendation 4S 200-250A BMS for RV?

JohanB

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Nov 10, 2019
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I am ordering 4pcs 272Ah Lishen cells to add capacity to my current setup in my van with 4S 150A lifepo4 with Daly 200A BMS. I have 300W solar, Epever 30A MPPT, 2500W inverter/charger, shunt battery monitor and would like to use it with up to 180A load shorter periods (induction cook top). Even though I will most likely not end up drawing 180A from one battery bank, I would still like to have the capacity if needed. Trying to figure out which BMS to go for? I spent hours and hours researching this forum and Youtube but still not sure. I would prefer to have functioning easy bluetooth with android, but display could also be ok. Active balancing would be nice, but I guess it is not necessary for my application. Low temp cut off would nice as well, even if I have setup the MPPT with temp sensor and cut off, I do not charge from the alternator and I can choose not to connect to AC when it is too cold.

Overkillsolar or JBD seems perfect, but as far as I have found they do not have any +150A models. First I thought Daly smart BMS would be a good option, but it seems to be lots of problems with these from what I see on this forum. Or was that only in the beginning and is solved now? Been looking at Chargery as well, but there seems to be some uncertainty about how it works at low voltage in a 4S setup. Plus all the wiring with shunt, relay and display seems to be a bit of a hassle. I would love it if it was an easy plug and play.

Do you have any recommendations?

Are there any other good options I am not aware of? Or are my concerns about Daly or Chargery maybe not too much to worry about?
 
Im in a similar boat.

I’ve purchases two of the jbd 150a units. To run two 4s banks. This way I’m hoping that I’ll be able to run up to 300a across the two banks.

I’m not sure that pulling 200a to 500a from eve batteries will be good for their life span . I’m interested in opinions here.

ive also read the bad Daly press. That had me concerned. However I really do like the the heat sink on the Daly’s.

that said I guess a Bms should strictly not run hot and is beat designed to run in the cool zone.

I’ve used the jbd units previously and I do like the app. I already have the payed version of the IOS app which I like. Feed back on the Daly is the software for the Daly is RS.

back to heat sinking. I’m thinking a well heat sinked jbd May go some way to matching the daly. I finger the internals of the jbd are probably similar to the Daly . However Daly has provided huge amp capacity due to their huge heat sinks.
 
Im in a similar boat.

I’ve purchases two of the jbd 150a units. To run two 4s banks. This way I’m hoping that I’ll be able to run up to 300a across the two banks.

I’m not sure that pulling 200a to 500a from eve batteries will be good for their life span . I’m interested in opinions here.

ive also read the bad Daly press. That had me concerned. However I really do like the the heat sink on the Daly’s.

that said I guess a Bms should strictly not run hot and is beat designed to run in the cool zone.

I’ve used the jbd units previously and I do like the app. I already have the payed version of the IOS app which I like. Feed back on the Daly is the software for the Daly is RS.

back to heat sinking. I’m thinking a well heat sinked jbd May go some way to matching the daly. I finger the internals of the jbd are probably similar to the Daly . However Daly has provided huge amp capacity due to their huge heat sinks.
Thanks for your response! Have you received your 150A jbd units yet? Did some research on them today and the boards are really big with solid terminals, but heat sink wise it does not look very promising. I read a review at Aliexpress with someone claiming it got really hot at 40A coninous. I have not found any reports on these here on the forum. If it is somewhat easy to mount additional heat sink and they really can handle 150A I might go for these as well.
 
Are there any other good options I am not aware of? Or are my concerns about Daly or Chargery maybe not too much to worry about?

For ease I would go for Daly smart BMS - 200A - they have fixed them pretty much .. make sure you get the latest generation with a fan ...

For best of bred (within your scope) I would go with Chargery ... yes its a little cumbersome to setup BUT once you do - it out runs most of them ...

so I guess flip a coin
 
I am hoping you mean 3000W - :oops: -- 300W solar would be like trying to fill a tanker with a water hose .
Haha, I do mean 300W. It's a tiny van with roof vents on the roof so I'm actually pretty happy I managed to get the 300 panel to fit. Apart from the induction cook top I only have very low consumptions and I have propane as backup.
 
For ease I would go for Daly smart BMS - 200A - they have fixed them pretty much .. make sure you get the latest generation with a fan ...

For best of bred (within your scope) I would go with Chargery ... yes its a little cumbersome to setup BUT once you do - it out runs most of them ...

so I guess flip a coin
Thank you! I did some more research and all these report with inaccurate SOC with low amps draws on the Chargery seems really annoying to me. Haven't found any reported solutions to that? I will be idling a couple of amps for a lot of the time, so I expect it will drift off for me.
 
Haha, I do mean 300W. It's a tiny van with roof vents on the roof so I'm actually pretty happy I managed to get the 300 panel to fit. Apart from the induction cook top I only have very low consumptions and I have propane as backup.
have 310 watt on the roof of my rv it is even extending out a bit but hey i had cold beer during the summer when it was 39c :)
12v compressor fridge
daly 250ah smart bms still need to test
 
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Thank you! I did some more research and all these report with inaccurate SOC with low amps draws on the Chargery seems really annoying to me. Haven't found any reported solutions to that? I will be idling a couple of amps for a lot of the time, so I expect it will drift off for me.

drop @Steve_S a note and ask him about Chargery ... he is the chargery expert .. they may have fixed many of the issues ... @Chargery sometimes answers questions but Steve is really the POC for knowledge
 
I do not recommend specific BMS' to anyone anymore, simply because I get dumped on if it's not what they think, want or if it falls short of their expectations.

There are a few good options out there, the JBD's are good and Overkill Solar does amazing support for the models they sell. I just got a 12V/120A 4S JBD with PC-Uart for my Powerhouse furnace battery pack, so I'll be trying that out. Heltec makes good BMS' as does LLT. Chargery's are good and with the relay/contactors, there are other advantages / disadvantages.

You have a situation to ponder on though.
I am ordering 4pcs 272Ah Lishen cells to add capacity to my current setup in my van with 4S 150A lifepo4 with Daly 200A BMS. I have 300W solar, Epever 30A MPPT, 2500W inverter/charger, shunt battery monitor and would like to use it with up to 180A load shorter periods
So you will have a "bank" with 2 batteries in parallel. 1x150A existing & 1x 272A new, 422Ah gross. 300W solar & 30A charger will fall short.
150AH battery can take 75A and 272AH can take 136A charge @ 0.5C. The lowest common denominator rules as you cannot exceed its capacities. and should handle 211A Discharge @ 12V. They can handle 1C generally for short bursts. See Cell Specs - Docs.
The batteries will split Load & Charge but will accept charge current relative to their capacity, so you will see the bigger battery absorb more amperage during charge.
The smaller battery WILL disconnect for LVD before the larger one if used to that point. It will also reach HVD before the larger one during charging. Therefore it is strongly suggested that whatever BMS you select, is capable of handling the full Load/Charge potentials as a single entity.
You will want to be able to adjust the BMS' (much easier if they are an identical type) so their cutoffs and settings account for the capacity differences.
2500W @ 12V is 208A uncorrected. HF Inverters can do 2X surge and LF Inverters can do 3X surge.

Hope it helps, Good Luck.
 
Thanks for your response! Have you received your 150A jbd units yet? Did some research on them today and the boards are really big with solid terminals, but heat sink wise it does not look very promising. I read a review at Aliexpress with someone claiming it got really hot at 40A coninous. I have not found any reports on these here on the forum. If it is somewhat easy to mount additional heat sink and they really can handle 150A I might go for these as well.
I ordered two of the 150a units ann Bk out a week back from jbd’s Ali store.

I’m in Australia and expect my Ali order to arrive some time in March or April. Ali orders to Australia seem to travel on ships that circle the earth at least three times before landing at an Australian port furtherest from my city.

Im keen to understand the physical differences between the 150a and the 120a jbd version. Seems like very different construction on the 150a compared to the 120a.

confusing as their is also a 100a version that looks the same as the 150a.
 
I am ordering 4pcs 272Ah Lishen cells to add capacity to my current setup in my van with 4S 150A lifepo4 with Daly 200A BMS. I have 300W solar,
Add capacity has two methods, paralle more cells or parallel more battery bank, for cells with different capacity, the former is not workable, the latter is only choice, but charge or discharge two battery banks with different capacity by one charger or loader, still have some problems, first need individual BMS monitor each battery bank, second how to parallel two battery banks need cosider seriously, the best is two battery banks fit with individual switch, charge and discharge will be conducted one by one, when small capacity battery bank finished charge, large capacity battery bank can be charged continuously, when small capacity battery bank stop discharging, large capacity battery bank can be discharged continuously, to realize charge and discharge switching between both battery banks automatically need a smart control system. and have to avoid two battery banks charge and discharge each other.
Good luck
 
Add capacity has two methods, paralle more cells or parallel more battery bank, for cells with different capacity, the former is not workable, the latter is only choice, but charge or discharge two battery banks with different capacity by one charger or loader, still have some problems, first need individual BMS monitor each battery bank, second how to parallel two battery banks need cosider seriously, the best is two battery banks fit with individual switch, charge and discharge will be conducted one by one, when small capacity battery bank finished charge, large capacity battery bank can be charged continuously, when small capacity battery bank stop discharging, large capacity battery bank can be discharged continuously, to realize charge and discharge switching between both battery banks automatically need a smart control system. and have to avoid two battery banks charge and discharge each other.
Good luck
Wow thank you so much for the generous information @Chargery !
That does sound like a bit of a hassle the way you describe it. Even though most days I am pretty sure I would be ok with only the 280Ah and the 150 would be kind of a back-up. May I ask why you do not recommend two banks with separate BMS and different capacity continuously connected in parallel? I have been scanning through other posts about this in the forum and on youtube and come to the conclusion that it most likely will work as long as each battery have enough capacity. Will there be currents running between the banks for some reason causing damage or wear?

Bear with me if my questions are a bit basic, I am kind of a newbie both with solar power and DC systems. I do believe I have the ability and willingness to learn and understand though. I even have a MsC degree in vehicle engineering, but that does not help me a lot with these practical things.

When I bought my first 4 150Ah cells I was not aware that I could have gotten 280 for the same price. Now I was first planning to get another 150Ah set, but when realising I can get 280 for pretty much the same $ and I have space for it it seems ridiculous to not go for 280. I am also actually considering getting another 4 pcs of 280 cells and use the 150 kit for something else.

May I ask three questions about the Chargery BMS that maybe @Chargery or @Steve_S can help me with? I am considering getting one of these, but been hesitating because of complexity, cost and some reported issues.
1. I've read reports of problems with SOC accuracy and as far as I understood the provided shunts not being able to register low currents. And using other shunts causes calibration issues. Is this still an issue or has it been solved? If so what is the lowest A the 300A shunt can register?
2. Can I trust the BMS functionaly for a 4S bank down to 11V? I'm ok with display light and buzzer not hanging in there.
3. If I choose to get 4 more 280Ah cells, can I use one BMS to control a 2P4S 12V 560Ah bank?

Lots of gratitude for the support and best holiday wishes from Sweden!
 
I do not recommend specific BMS' to anyone anymore, simply because I get dumped on if it's not what they think, want or if it falls short of their expectations.

There are a few good options out there, the JBD's are good and Overkill Solar does amazing support for the models they sell. I just got a 12V/120A 4S JBD with PC-Uart for my Powerhouse furnace battery pack, so I'll be trying that out. Heltec makes good BMS' as does LLT. Chargery's are good and with the relay/contactors, there are other advantages / disadvantages.

You have a situation to ponder on though.

So you will have a "bank" with 2 batteries in parallel. 1x150A existing & 1x 272A new, 422Ah gross. 300W solar & 30A charger will fall short.
150AH battery can take 75A and 272AH can take 136A charge @ 0.5C. The lowest common denominator rules as you cannot exceed its capacities. and should handle 211A Discharge @ 12V. They can handle 1C generally for short bursts. See Cell Specs - Docs.
The batteries will split Load & Charge but will accept charge current relative to their capacity, so you will see the bigger battery absorb more amperage during charge.
The smaller battery WILL disconnect for LVD before the larger one if used to that point. It will also reach HVD before the larger one during charging. Therefore it is strongly suggested that whatever BMS you select, is capable of handling the full Load/Charge potentials as a single entity.
You will want to be able to adjust the BMS' (much easier if they are an identical type) so their cutoffs and settings account for the capacity differences.
2500W @ 12V is 208A uncorrected. HF Inverters can do 2X surge and LF Inverters can do 3X surge.

Hope it helps, Good Luck.
Thank you so much @Steve_S ! I am aware of my low solar charging capacity, but as I already mentioned that is what I can fit on my roof. And it is surely better than nothing. I have a 40A AC charger to top up with as well and I am definitely expecting to need this especially during the darker months. The 180A max draw is based on estimated highest load on the inverter at full power of the induction hub 1800W which means about 165Ato the inverter + compressor fridge and some led lights on the DC side. That will be pretty rare occasions and only a few minutes at the time. I am only expecting to use 30-60Ah / 24h without the induction hob, that I only plan to use when I have enough solar power.

As I already mentioned I'm a rookie on this, but I'm eager to learn more. May I ask what would be the problem with the smaller bank reaching HVB before the larger bank? If it automatically disconnects? Would it be a problem if the larger bank keep charging a bit longer with the smaller bank disabled by the BMS? Same with LVB during discharge, even if I am not planning to go there.

You mention advantages and disadvantages with relays - what do you think would be the advantages and disadvantages with the Chargery system with relays for my application? Would I be best off getting the DCC as well for simplicity and to be safe?

Thanks again and greetings from Sweden
 
I do not recommend specific BMS' to anyone anymore, simply because I get dumped on if it's not what they think, want or if it falls short of their expectations.

There are a few good options out there, the JBD's are good and Overkill Solar does amazing support for the models they sell. I just got a 12V/120A 4S JBD with PC-Uart for my Powerhouse furnace battery pack, so I'll be trying that out. Heltec makes good BMS' as does LLT. Chargery's are good and with the relay/contactors, there are other advantages / disadvantages.

You have a situation to ponder on though.

So you will have a "bank" with 2 batteries in parallel. 1x150A existing & 1x 272A new, 422Ah gross. 300W solar & 30A charger will fall short.
150AH battery can take 75A and 272AH can take 136A charge @ 0.5C. The lowest common denominator rules as you cannot exceed its capacities. and should handle 211A Discharge @ 12V. They can handle 1C generally for short bursts. See Cell Specs - Docs.
The batteries will split Load & Charge but will accept charge current relative to their capacity, so you will see the bigger battery absorb more amperage during charge.
The smaller battery WILL disconnect for LVD before the larger one if used to that point. It will also reach HVD before the larger one during charging. Therefore it is strongly suggested that whatever BMS you select, is capable of handling the full Load/Charge potentials as a single entity.
You will want to be able to adjust the BMS' (much easier if they are an identical type) so their cutoffs and settings account for the capacity differences.
2500W @ 12V is 208A uncorrected. HF Inverters can do 2X surge and LF Inverters can do 3X surge.

Hope it helps, Good Luck.
Btw, regarding the other options you mention: I do not find a lot of reports about the 150A version of JBD. And as far as I can see it is a huge PCB with tiny heat sink. Unfortunately I do not find any 150+A 4S versions of Heltecc or LLT with smart function or display, or any option to change parameters. And they do not seem to have low temp charge limits. I guess you are not a fan of Daly since you did not mention them?
 
@JohanB
I run 175 & 280 in one bank. I have put these through a serious test phase and they are also my production power. The practical observations are simple enough.
If I am pushing 75A charge at the bank, the 280's will take in 20-23A+/- each, the 175's will split the difference as 17A+/-. That is starting at roughly 20% SOC on each battery in the bank.
The "tricky" part comes as they start getting full. 175-1 hit's HVD (High Volt Disconnect) because one cell trips it. That 17A now shifts to the rest of the packs. Now there goes 175-2 because the boost caused a runner to trip LVD. This is common when cells are reaching their full state, a runner is not unexpected with these commodity cells. Now I have 30A extra being divided by the two 280's, who are pulling in 30-35A each.
Next, the two 175's have settled a bit, the contactor closes and they start charging again, that is until the runner pops up & triggers HVD.
Shortly after this starts with the 175's, the 280's start the same routine.

This is where the SHTF !
4 Battery packs in one bank, 2 different AH ratings. BMS' cycling on/off because batteries are either "full" or runners are triggering HVD.*
Charging & using current (Amperage) to determine when a pack is "full" by reduced amps taken does, not work It is "reading" 4 packs cumulatively, so it is invalid.
Charging and using voltage from the bank to determine "full" state. So once the "bank" reaches 28.0V call it a day, it's done (I'm 24V so).

The Uglies is nasty potential that can freak a few out.
Chargers DO NOT LIKE hard charging drops ! ie complete cutoffs at once. Most "chargers" can handle it well though, but the cheapo "value" deals, I'd say be prepared to replace it.
Inverter/Charger like my Samlex EVO do not appreciate it either, a hard drop causes it to do a fast reset cycle, triggered by it's internal relays. BTW: They have a very loud Snap.
Generators (as I use that for hard charging) REALLY hate that ! dropping 120V/21A +/-3 to run 24V/75A gives the ol Genny a shudder !

* HVD is not the only cause for triggers at this stage, Set Voltage difference allowed between cells by default is 20 or 30mv depending on BMS and programming. These cells can & do diverge as they get into higher voltage ranges above 3.400. It is not uncommon to see up to 1mv per AH (280mv - 280AH cell)

~~~ end of my observations
150 & 280. close enough but you only have 1 of each, so that's more controlled.
The cells will deviate and likely a runner will appear, quite quickly.
The 150 will reach low voltage & disconnect before the 280.
The BMS' have to ensure that the pack disconnects at no lower than 2.75V per cell.
The 280 will continue till it reaches low volt. Make sure the Inverter voltage cutoff is slightly above the battery cutoff. 11V at battery, 11.2V at Inverter for cutoff, or similar.
When charging, the 150 will hit full first, then the 280. Set Voltage cutoff no higher than 13.8 (for 12V bank) but watch and pay attention if the BMS cuts off at a lower voltage and adjust charger accordingly.

Relays are a PITA, the DCC is a lifesaver. I use the Chargery's and they do their job. It's not "perfect" but then most of the BMS' out there aren't. Jason has Listened & Heard the feedback and solutions / options posed and has done his best to incorporate things. Something few vendors do, especially when everything has to be translated back & forth. That says something. He's also about to release some new BMS' and goodies, based on a lot of input from here as well.

I have no opinion on Daly, there is Good & Bad about them but that's like all the others too. They have also made major strides in teh past year and improved / expanded their product lines.

The JBD I got was sent direct from the factory. The only reason I chose a large amp for it was in case I need it for something in an emergency. I have to be able to use all things in 3 different ways... I am quite Rural & Remote, these things must be taken into acccount always. It is similar but not identical to what Overkill Solar is selling.

hope it helps, good luck
BTW, look at the links in my signature, some may help you.
 
@JohanB
I run 175 & 280 in one bank. I have put these through a serious test phase and they are also my production power. The practical observations are simple enough.
If I am pushing 75A charge at the bank, the 280's will take in 20-23A+/- each, the 175's will split the difference as 17A+/-. That is starting at roughly 20% SOC on each battery in the bank.
The "tricky" part comes as they start getting full. 175-1 hit's HVD (High Volt Disconnect) because one cell trips it. That 17A now shifts to the rest of the packs. Now there goes 175-2 because the boost caused a runner to trip LVD. This is common when cells are reaching their full state, a runner is not unexpected with these commodity cells. Now I have 30A extra being divided by the two 280's, who are pulling in 30-35A each.
Next, the two 175's have settled a bit, the contactor closes and they start charging again, that is until the runner pops up & triggers HVD.
Shortly after this starts with the 175's, the 280's start the same routine.

This is where the SHTF !
4 Battery packs in one bank, 2 different AH ratings. BMS' cycling on/off because batteries are either "full" or runners are triggering HVD.*
Charging & using current (Amperage) to determine when a pack is "full" by reduced amps taken does, not work It is "reading" 4 packs cumulatively, so it is invalid.
Charging and using voltage from the bank to determine "full" state. So once the "bank" reaches 28.0V call it a day, it's done (I'm 24V so).

The Uglies is nasty potential that can freak a few out.
Chargers DO NOT LIKE hard charging drops ! ie complete cutoffs at once. Most "chargers" can handle it well though, but the cheapo "value" deals, I'd say be prepared to replace it.
Inverter/Charger like my Samlex EVO do not appreciate it either, a hard drop causes it to do a fast reset cycle, triggered by it's internal relays. BTW: They have a very loud Snap.
Generators (as I use that for hard charging) REALLY hate that ! dropping 120V/21A +/-3 to run 24V/75A gives the ol Genny a shudder !

* HVD is not the only cause for triggers at this stage, Set Voltage difference allowed between cells by default is 20 or 30mv depending on BMS and programming. These cells can & do diverge as they get into higher voltage ranges above 3.400. It is not uncommon to see up to 1mv per AH (280mv - 280AH cell)

~~~ end of my observations
150 & 280. close enough but you only have 1 of each, so that's more controlled.
The cells will deviate and likely a runner will appear, quite quickly.
The 150 will reach low voltage & disconnect before the 280.
The BMS' have to ensure that the pack disconnects at no lower than 2.75V per cell.
The 280 will continue till it reaches low volt. Make sure the Inverter voltage cutoff is slightly above the battery cutoff. 11V at battery, 11.2V at Inverter for cutoff, or similar.
When charging, the 150 will hit full first, then the 280. Set Voltage cutoff no higher than 13.8 (for 12V bank) but watch and pay attention if the BMS cuts off at a lower voltage and adjust charger accordingly.

Relays are a PITA, the DCC is a lifesaver. I use the Chargery's and they do their job. It's not "perfect" but then most of the BMS' out there aren't. Jason has Listened & Heard the feedback and solutions / options posed and has done his best to incorporate things. Something few vendors do, especially when everything has to be translated back & forth. That says something. He's also about to release some new BMS' and goodies, based on a lot of input from here as well.

I have no opinion on Daly, there is Good & Bad about them but that's like all the others too. They have also made major strides in teh past year and improved / expanded their product lines.

The JBD I got was sent direct from the factory. The only reason I chose a large amp for it was in case I need it for something in an emergency. I have to be able to use all things in 3 different ways... I am quite Rural & Remote, these things must be taken into acccount always. It is similar but not identical to what Overkill Solar is selling.

hope it helps, good luck
BTW, look at the links in my signature, some may help you.
Wow, thank you so much for this super detailed informative information, so valuable to me! For solar charging I should be fine with setting up my MPPT. My chinese inverter/charger though does not have any options to customize cutoff values (as far as I know) and according to the spec it doesn't cut off until 10.0V and charges to 14.5V. And I will also run a 12V circuit with fridge and lights and stuff. My current Daly not so smart BMS for the 150Ah pack I believe is set to 2.5 LVD that I do not think I can change. Some challenges! Overall I guess I would be ok with solar charging and manually monitoring not going too low in SOC. I have a shunt capacity monitor. And guess I can set up a low voltage alarm.

Anyways thank you so much for the support!
 
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