paulmurdoch
New Member
- Joined
- Dec 17, 2020
- Messages
- 36
Hello,
Ive posted before explaining how I want to make a power wall using x28 LG chem 48V in x4 14S parallel configuration (56KW) for my offgrid house, each of the 4 will have a Daly 14S BMS. These are the same LG chem batteries, which battery hook up are selling once again. My new question is my offgrid house is a long ways a way, and the current lead acid batteries are dead (This is a new house I just purchased)
My plan is travel to the house, then during a 4 day window, configure the lithium batteries and use the existing inverter and charge controller from the lead acid batteries system. The charge controllers x2 are the Xantrex W60 MPPT which seem to have a robust configuration system, where equalization can be disabled, Bulk & Absorption V can be set and float can be disabled. Is it practical to use this charge controller for these type of Lithium Ion batteries? If so what would be the recommended settings?
My next question is a tad more difficult. I have no idea of the voltage of these batteries and I need to safely balance them without any power being available. My plan is to open each one up and remove the internal BMU, parallel the x2 7 cells to make a 2S from each LG battery. I believe putting them in parallel at this point, will be ok as the BMU is still balancing these cells. My problem is I want to then series 7 of these units to form the 14S, and install a 200amp daly BMS. My problem is how can I balance these large batteries before placing them in series without power to charge? I thought of the obvious, but I'm unsure about linking these in parallel to self balance. I also thought about using the charge controller to charge each cell independently. This might be the best way to go, but I'm not sure if I have enough time.
I would appreciate any advice.
Thanks!
Ive posted before explaining how I want to make a power wall using x28 LG chem 48V in x4 14S parallel configuration (56KW) for my offgrid house, each of the 4 will have a Daly 14S BMS. These are the same LG chem batteries, which battery hook up are selling once again. My new question is my offgrid house is a long ways a way, and the current lead acid batteries are dead (This is a new house I just purchased)
My plan is travel to the house, then during a 4 day window, configure the lithium batteries and use the existing inverter and charge controller from the lead acid batteries system. The charge controllers x2 are the Xantrex W60 MPPT which seem to have a robust configuration system, where equalization can be disabled, Bulk & Absorption V can be set and float can be disabled. Is it practical to use this charge controller for these type of Lithium Ion batteries? If so what would be the recommended settings?
My next question is a tad more difficult. I have no idea of the voltage of these batteries and I need to safely balance them without any power being available. My plan is to open each one up and remove the internal BMU, parallel the x2 7 cells to make a 2S from each LG battery. I believe putting them in parallel at this point, will be ok as the BMU is still balancing these cells. My problem is I want to then series 7 of these units to form the 14S, and install a 200amp daly BMS. My problem is how can I balance these large batteries before placing them in series without power to charge? I thought of the obvious, but I'm unsure about linking these in parallel to self balance. I also thought about using the charge controller to charge each cell independently. This might be the best way to go, but I'm not sure if I have enough time.
I would appreciate any advice.
Thanks!