Interesting. I feel that it is better to have all batteries connected and charging even if this means the currents are lower and that the bank never gets fully charged as this is likely to extend the life of the bank overall. As a comparison, I have two banks of 4 batteries in series/parallel for 48V. One bank is 100Ah batteries and the other is 280Ah giving me a grand total of 380Ah which is programmed into my smartshunt. The two banks are simply joined together in parallel using 120A Anderson connectors and appropriate fuses and switchgear. This lot feeds a 3000W hybrid inverter which has a built-in 15A 48V charger and it automatically switches between solar/utility/battery as and when necessary. My solar input is 1200W and I get a lot of shading in November/December/January/February when the input is less that my usage and the charger runs daily until the sun comes around again. Because of this layout my wiring is much simpler than yours for which I am greatful. 🙂
Absolutely, I agree. It is perfectly ok to charge or discharge LiFePO4 batteries at very slow rates. The best configuration is to simply leave all the batteries tied together. Not only is this fine to do, but ultra low C-rates result in very high round-trip battery efficiencies that often exceed 97%. It is very common in solar systems for charge and discharge rates to be under 0.05C.
Okay where to start first off good quality video, secondly I don’t really understand why you would need this setup if you where to combine those banks you would have 600 amphours off capacity and the charge that you put in would be the same as in 2 separate banks. What you talked about about limited space is true but it the 200w per 100ah is not a hard limit it does not matter that there is less solar it just means from 0% it would take longer to fully charge. Another problem you will weave is with the smartshunt it is measuring currant in from solar, currant in from charger, currant out for the inverter, so this is because the shut reads the currant on the negative side. This is not switched over. I hover this comment makes sense
So a better setup unless there are other reasons. Would be combine the banks, connect the mppt, and charger (it doesn’t matter that it is connected when off) and adjust the smartshunt settings to 600ah
Hi, thanks for taking time to comment. I made this set up in response to questions I get asked and wanted to see what was possible to make most efficient use of limited solar input. I used to have all 6 batteries connected as you described with smart shunt set for 600ah albeit still in 2 banks of 3 again staying within bms limits. Its early days but so far Charging is more efficient there is less resistance of course and the batteries receive higher amps. I guess another factor is safety, if things went south it won't affect the other battery bank. I'm remaining within the capabilities of the jbd 100A Bms systems too and having more than 4 in parallel is pushing limits. I will see how it goes for a while and compare data from previously.
@@DCGUY You need to fuse and breaker the batteries properly, but that is the only safety concern. You can just leave all the batteries tied together with the appropriate topology, in one bank... the round-trip efficiency through the battery bank is actually better at lower C rates. Having huge battery banks with relatively small amounts of solar is not a problem at all. You don't lose any energy (you actually get more energy from the higher efficiency). Also, you should never use those manual battery 1 / battery 2 transfer switches under load. Well, you shouldn't use them at all really. They are not spring loaded or thermally protected. Basically a huge fire hazard that sneaks up on people. There is the further problem of the shunt potentially losing power when switching battery banks, which can really mess up its tracking. It really is best to not mess around trying to switch or swap battery banks. The battery charger can be setup in various ways. The most common setup when the grid is available is to just put it into a load-support mode. Basically put it in power supply mode set to a voltage that represents roughly a 30% state of charge so when the battery drops down to that voltage the charger kicks in and starts supplying support (usually its a slow ramp until eventually, after a few hours, the charger is providing 100% of the load).
@@DCGUY okay I don’t normally work with so many batteries in parallel but now that you mention it, I have indeed read in the manual that there is a limit of 4 batteries but I kind of forgot
@@junkerzn7312 thanks for taking time to comment, it's appreciated. It never occurred to me about putting the ip22 into power supply mode, something I need to look into more. Cheers 🍻
Just a quick question with the MRBF's you have used. Are the holders M10 holes with M8 studs? I can't find any M8 holes with M8 studs..... just curious
Negative from scc goes to main negative busbar as does the ac charge negative. Both banks go via smart shunt (negative side) as does the inverter negative.
Hi, great video. Is it possible to use two victron 500a shunts? so basically where both of your banks go through one shunt could you split that and use two shunts to get accurate information on both banks?
Hi, just a question regarding charging the Eco-Worthy 100ah batteries. I have the same Victron charger and I am getting confused about the correct settings for charging the batteries, please can I ask what settings you use. So much information going around about charging at lower voltage (14.2v - 3.55v per cell) than manufacturer specs 14.4v-14.6v and not fully charging the batteries to 100%. Would really appreciate your advice.
I know how confusing this can be as everyone has an opinion. I personally leave the charger on pre-set 7 lifepo4 and leave the BMS to look after the rest. Try to avoid the deep rabbit hole of playing with bulk, absorption, and float parameters as every cell varies from manufacturer to manufacturer, and victron know what they are doing.
@@DCGUY Yes gets very confusing when everyone has a different opinion. I don't have a pre-set 7 lifepo4 on the Victron charger? I have normal 14.4v, normal + recondition 14.4v, high 14.7v, high + recondition 14.7v, li-ion 14.2v? I have the Victron IP22 12/30 (1). Did you have any problems with the original BMS as I see you upgraded yours to the blue-tooth ones?
Sorry that was a typo, pre set 7 is what i use with the charge controller not the ip22 charger. The IP22 is pre set for Li On and that's what I use. I never had any issues with the original BMS units, I simply wanted to see a bit more data, hence I went with Bluetooth enabled units. However, I have since had one of these new JBD BT units fail and trying to figure out what failed and why. The BMS units I replaced are all compatible with a series connection but while testing a 48v hybrid inverter one of the new units went into weird mode. I've got replacement units but want to understand what failed and why.
@@DCGUY Ok perfect, thank you for letting me know, I will use that setting. I had a weird thing with a couple of these batteries whilst charging the first time, they went into absorption mode for about 30 minutes and then into bulk. The other batteries I have went straight into bulk charging, any ideas or anything to be concerned about? I'd like the bluetooth bms function to monitor but don't fancy stripping them down, how easy/hard was it to do?
@@BarryTRc Swapping BMS units was fairly straightforward for myself as I had already lost any warranty by stripping them down, so to keep warranty in place your best to just make do with what you have. As for some batteries going straight to bulk or absorption that's simply down to the pulse voltage read by the charger from the BMS and is nothing to worry about.
Great to see UK content with equipment we can get hold of. Very informative videos. All the best for the new year.
Thanks, you too!
Interesting. I feel that it is better to have all batteries connected and charging even if this means the currents are lower and that the bank never gets fully charged as this is likely to extend the life of the bank overall. As a comparison, I have two banks of 4 batteries in series/parallel for 48V. One bank is 100Ah batteries and the other is 280Ah giving me a grand total of 380Ah which is programmed into my smartshunt. The two banks are simply joined together in parallel using 120A Anderson connectors and appropriate fuses and switchgear. This lot feeds a 3000W hybrid inverter which has a built-in 15A 48V charger and it automatically switches between solar/utility/battery as and when necessary. My solar input is 1200W and I get a lot of shading in November/December/January/February when the input is less that my usage and the charger runs daily until the sun comes around again. Because of this layout my wiring is much simpler than yours for which I am greatful. 🙂
Absolutely, I agree. It is perfectly ok to charge or discharge LiFePO4 batteries at very slow rates. The best configuration is to simply leave all the batteries tied together. Not only is this fine to do, but ultra low C-rates result in very high round-trip battery efficiencies that often exceed 97%. It is very common in solar systems for charge and discharge rates to be under 0.05C.
Thanks for watching and taking time to comment, your input is greatly appreciated. Happy new year to you.
Really appreciate you taking time to comment, it's always good to know what others are doing and what works best for them. Happy new year to you.
Okay where to start first off good quality video, secondly I don’t really understand why you would need this setup if you where to combine those banks you would have 600 amphours off capacity and the charge that you put in would be the same as in 2 separate banks. What you talked about about limited space is true but it the 200w per 100ah is not a hard limit it does not matter that there is less solar it just means from 0% it would take longer to fully charge. Another problem you will weave is with the smartshunt it is measuring currant in from solar, currant in from charger, currant out for the inverter, so this is because the shut reads the currant on the negative side. This is not switched over. I hover this comment makes sense
So a better setup unless there are other reasons. Would be combine the banks, connect the mppt, and charger (it doesn’t matter that it is connected when off) and adjust the smartshunt settings to 600ah
Hi, thanks for taking time to comment. I made this set up in response to questions I get asked and wanted to see what was possible to make most efficient use of limited solar input. I used to have all 6 batteries connected as you described with smart shunt set for 600ah albeit still in 2 banks of 3 again staying within bms limits.
Its early days but so far Charging is more efficient there is less resistance of course and the batteries receive higher amps. I guess another factor is safety, if things went south it won't affect the other battery bank. I'm remaining within the capabilities of the jbd 100A Bms systems too and having more than 4 in parallel is pushing limits. I will see how it goes for a while and compare data from previously.
@@DCGUY You need to fuse and breaker the batteries properly, but that is the only safety concern. You can just leave all the batteries tied together with the appropriate topology, in one bank... the round-trip efficiency through the battery bank is actually better at lower C rates.
Having huge battery banks with relatively small amounts of solar is not a problem at all. You don't lose any energy (you actually get more energy from the higher efficiency).
Also, you should never use those manual battery 1 / battery 2 transfer switches under load. Well, you shouldn't use them at all really. They are not spring loaded or thermally protected. Basically a huge fire hazard that sneaks up on people.
There is the further problem of the shunt potentially losing power when switching battery banks, which can really mess up its tracking. It really is best to not mess around trying to switch or swap battery banks.
The battery charger can be setup in various ways. The most common setup when the grid is available is to just put it into a load-support mode. Basically put it in power supply mode set to a voltage that represents roughly a 30% state of charge so when the battery drops down to that voltage the charger kicks in and starts supplying support (usually its a slow ramp until eventually, after a few hours, the charger is providing 100% of the load).
@@DCGUY okay I don’t normally work with so many batteries in parallel but now that you mention it, I have indeed read in the manual that there is a limit of 4 batteries but I kind of forgot
@@junkerzn7312 thanks for taking time to comment, it's appreciated. It never occurred to me about putting the ip22 into power supply mode, something I need to look into more. Cheers 🍻
I don't see the purpose of splitting the battery bank in half. The solar charging power is the same either way.
You are correct, it is just a way to re-charge one bank more effeciently and faster.
Just a quick question with the MRBF's you have used. Are the holders M10 holes with M8 studs? I can't find any M8 holes with M8 studs..... just curious
Yes, it seems that they come with m10 as the main connection.
Show what you did with the negatives in that system.
Negative from scc goes to main negative busbar as does the ac charge negative. Both banks go via smart shunt (negative side) as does the inverter negative.
Hi, great video. Is it possible to use two victron 500a shunts? so basically where both of your banks go through one shunt could you split that and use two shunts to get accurate information on both banks?
Yes you can use 2 separate shunts just connect main negative feed from each bank to its own shunt then onto a main negative busbar.
@@DCGUY Great, thank you for letting me know, really appreciate it.
Hi, just a question regarding charging the Eco-Worthy 100ah batteries. I have the same Victron charger and I am getting confused about the correct settings for charging the batteries, please can I ask what settings you use. So much information going around about charging at lower voltage (14.2v - 3.55v per cell) than manufacturer specs 14.4v-14.6v and not fully charging the batteries to 100%. Would really appreciate your advice.
I know how confusing this can be as everyone has an opinion. I personally leave the charger on pre-set 7 lifepo4 and leave the BMS to look after the rest. Try to avoid the deep rabbit hole of playing with bulk, absorption, and float parameters as every cell varies from manufacturer to manufacturer, and victron know what they are doing.
@@DCGUY Yes gets very confusing when everyone has a different opinion. I don't have a pre-set 7 lifepo4 on the Victron charger? I have normal 14.4v, normal + recondition 14.4v, high 14.7v, high + recondition 14.7v, li-ion 14.2v? I have the Victron IP22 12/30 (1). Did you have any problems with the original BMS as I see you upgraded yours to the blue-tooth ones?
Sorry that was a typo, pre set 7 is what i use with the charge controller not the ip22 charger. The IP22 is pre set for Li On and that's what I use. I never had any issues with the original BMS units, I simply wanted to see a bit more data, hence I went with Bluetooth enabled units. However, I have since had one of these new JBD BT units fail and trying to figure out what failed and why. The BMS units I replaced are all compatible with a series connection but while testing a 48v hybrid inverter one of the new units went into weird mode. I've got replacement units but want to understand what failed and why.
@@DCGUY Ok perfect, thank you for letting me know, I will use that setting. I had a weird thing with a couple of these batteries whilst charging the first time, they went into absorption mode for about 30 minutes and then into bulk. The other batteries I have went straight into bulk charging, any ideas or anything to be concerned about? I'd like the bluetooth bms function to monitor but don't fancy stripping them down, how easy/hard was it to do?
@@BarryTRc Swapping BMS units was fairly straightforward for myself as I had already lost any warranty by stripping them down, so to keep warranty in place your best to just make do with what you have. As for some batteries going straight to bulk or absorption that's simply down to the pulse voltage read by the charger from the BMS and is nothing to worry about.