Daly BMS gone crazy..Update Opinions
I was charging my 120ah lifepo4 battery yesterday and came in for lunch and saw it shut down..I figured it hit the 3.65 volt cell limit and shut down,I went out to check it and saw this on the Blueto...
Forum Discussion
From the search suggest by FWD
https://www.sciencedirect.com/science/article/abs/pii/S0378775310014898
Abstract
Degradation of a high capacity prismatic LiFePO4 cell with deep cycling at elevated temperature of 50 °C is studied by electrochemical impedance spectroscopy as well as capacity and power fading characterization at different test temperatures (45, 25, 0 and ?10 °C). Capacity fade after 600 cycles is 14.3% at 45 °C and 25.8% at ?10 °C. There is little power fade at 45 °C after 600 cycles, whereas the power fade after 600 cycles is 61.6% and 77.2%, respectively, at 0 and ?10 °C. The capacity and power fade evidently becomes more severe at lower temperature. In particular, the power fade at low temperatures (e.g., 0 and ?10 °C) rather than capacity loss is a major limitation of the LiFePO4 cell. The primary mechanism for capacity fade is loss of cyclable lithium in the cell resulting from lithium-consuming solid electrolyte interphase (SEI) layer growth and side reactions. The increased interfacial resistance (Rw) due to the catalytic growth of SEI layer on the graphite anode and increased electrolyte resistance are the main sources for power fade.
If I am reading that correctly LI are not well suited to cool temperatures and the loss of capacity is permanent?
https://www.sciencedirect.com/science/article/abs/pii/S0378775310014898
Abstract
Degradation of a high capacity prismatic LiFePO4 cell with deep cycling at elevated temperature of 50 °C is studied by electrochemical impedance spectroscopy as well as capacity and power fading characterization at different test temperatures (45, 25, 0 and ?10 °C). Capacity fade after 600 cycles is 14.3% at 45 °C and 25.8% at ?10 °C. There is little power fade at 45 °C after 600 cycles, whereas the power fade after 600 cycles is 61.6% and 77.2%, respectively, at 0 and ?10 °C. The capacity and power fade evidently becomes more severe at lower temperature. In particular, the power fade at low temperatures (e.g., 0 and ?10 °C) rather than capacity loss is a major limitation of the LiFePO4 cell. The primary mechanism for capacity fade is loss of cyclable lithium in the cell resulting from lithium-consuming solid electrolyte interphase (SEI) layer growth and side reactions. The increased interfacial resistance (Rw) due to the catalytic growth of SEI layer on the graphite anode and increased electrolyte resistance are the main sources for power fade.
If I am reading that correctly LI are not well suited to cool temperatures and the loss of capacity is permanent?
