Lifepo4 replacement quandary

Having spent much time reading posts on LiPo4 batteries, I've come to the conclusion that's the way I want to progress away from LA technology. Reading between the lines it would seem prysmatic cells are the way to go, the search for cells is overwhelming, I've been in contact with suppliers many of whom are willing to sell the cells but have no BMS system designed and or supplied by them, which means an after market BMS, not that that's a problem, it just when something goes wrong each will blame the other for the failure, should it happen. There is one supplier who has an integrated battery with BMS claiming up to 4 series 4 parrallel with their 12V 180 Ah batteries each of which has its own BMS, not sure how that works, here is the link to the supplier https://www.alibaba.com/product-detail/Polinovel-Latest-HD-12v-24v-180ah_60777826187.html?spm=a2700.galleryofferlist.normalList.11.1cdc65caXXOdg0&s=p Which way to go is the question. Oh yes China supplier, but when in Asia shop in Asia.
1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Comments
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
https://www.alibaba.com/product-detail/Long-cycle-life-Rechargeable-100Ah-lifepo4_60725516304.html?spm=a2700.7724838.2017115.35.4f7a4665cgN8cb
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
That is an unbelievably good price. In the states the equivalent would be over $1000 more. And I know you're going to be amazed when you start using then. Did you get a charger to balance them yet? The initial balance is the most critical aspect of using a LFP bank IMO. Mine has been in service a little over 2 years now. Let me know if I can assist in any way with the installation.
Rick
No not yet, wlii be speaking to the supplier about a BMS, will ask him, you mean a charger to charge each cell individually I assume.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
Rick
- Instruct the charge controller or inverter via a hardware/software interface to stop charging/discharging when it detects that any cell has gone outside it safe operating conditions.
- Raise an alarm which requires a person to intervene and shutdown the inverter or charge controller.
- In the event of any cell voltage going too high stop the charge controller charging the battery by preferably disconnecting the solar panels from the controller or disconnecting the battery from the charge controller or in the event of any cell voltage going too low disconnect the inverter from the charge controller.
IMO it is best to have a BMS that uses method 1 with as a backup if the charge controller or inverter does not shutdown when instructed to resort to method 3. I think ta BMS should also raise an alarm that a fault has occurred even if the fault is resolved by the BMS.32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
Ivor
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
The screen is from one of the best in the world at this, in so many applications!
http://members.sti.net/offgridsolar/
E-mail [email protected]
Rick
Simon, the reference to software control was to do with the use of data to comand a function, specifically with regards to fire alarm systems, where a physical relay contact is required as a fail safe, to shut down ventilation fans for example. Direct digital control , DDC, engineers always wanted to use digital input to their systems to shut down equipment over a LAN network, not fail safe. Also the transmission of alarm signals couldn't be transmitted via a VOIP telco system, it had to be physical land line, that is changing however with the use of multiple communication means to monitor each other, VOIP and cellular as examples, times are changing and physical land lines are fast becoming a thing of the past. The use of mechanical relays to disconnect charge and discharge, as apposed to internal mosfets, or other means, would make it reletivaly easy to include a second BMS simply as a monitor of the primary system, interlocked via a second contact in the relay coil circuit. Perhaps I'm over thinking this a little, but redundancy is not nesesarally a bad thing.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
modified BMS based on TI bq769x0 cell monitors.
Homemade overall system monitoring and power management https://github.com/simat/BatteryMonitor
There should only be 2 things that shut down power offgrid, it is a new wrinkle that the battery is a 3rd. My solution takes it back to a dead battery or overcurrent protection causing loss of power. I definitely would not use relays. Just protect your network cables or double them.
Take a look at JEHUGARCIA on Utube for some ideas. I would not do any of this but for hobbyist he is pretty popular. Typical Southern California mindset and he is kind of funny.
Currently testing a second battery / inverter and it's on the bypass of the power distribution panel. This gets us to a completely redundant power system which is nice. Since it is new and has low hours on it I have to watch it alot.
It sounds like you (mcgivor) are still thinking this out? Maybe just wait another year and see? I would not jump into this if you question all the work. As I have said, this (homebrew) is not for my clients and I just do not have the time for it. Good Luck
http://members.sti.net/offgridsolar/
E-mail [email protected]
I don't use the balancing method describe in the attachment, I use a single cell charger to get all the cells up to 3.38 to 3.4 volts then put them all in parallel with busbars. Or, if they are already close in balance, charge them in series up to the same voltage then put them in parallel. Once in parallel, they are charged with the 3.65 volt charger until they reach 3.6 volts. The charger I use for this is 10 amp.
IMO this initial balance is good for 2 or 3 years, at least that is what I found with my HiPower cells. A rebalance could be done when necessary, it just involves paralleling the bank as described before. I have tried using the rebalancing method Simon mentioned, manually draining individual cells with a resistor to bring them into balance, but it is a bit too tedious for my liking. So I stick to what works for me.
Rick
not thought about the need for an auto disconnect but I'll contact electric car parts for their perspective and update here.
before i move forward, I'm hoping to find a buyer for my batteries since they should have quite a bit of life left and i can't see just wasting them.