Consequences of abusing your lithium (LIFEPO4) leisure batteries

The subject of lithium cell aging has been well researched and studied over recent years and since the relatively recent commercialisation and wider use of this chemistry, aging studies have been undertaken under a wide range of conditions. One such research study that caught my eye was that of Song, H., Cao, Z., Chen, X. et al. J Solid State Electrochem (2013) 17: 599. https://doi.org/10.1007/s10008-012-1893-2 and published in the Journal of solid state electrochemistry.

Song et al. under took cyclic high charge and very high discharge rates of LiFePo4 cells at elevated temperature ranges. In practice this would be the equivalent to subjecting a KS Energy leisure battery to a force charge rate of 1C and a discharge rate of 3C within your motorhome (for example), on a hot summers day and also on hot day in a desert of some location. With a standard KS-100, this means charging it at 100Amps and discharging it at 300Amps at 25 degrees and 55 degrees respectively.

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We do not recommend you subject your KS Energy batteries to such abuse, however what if you did? Well Song et al. show that you could expect at 25 °C, the cell capacity decreased to 95 % of the initial capacity at around 600 cycles and with an increasing temperature of 55 °C, the cell capacity shows faster loss with a degradation to 70 % of the initial capacity. Later physical analysis of the cell showed that this was down to lithium loss within the cell as the lithium was irrecoverably converted to other substances.

Obviously charging and discharging your KS Energy batteries in this manner is certainly outside of our stated specifications for our batteries and will certainly void your warranty. Be that as it may, this is still an incredible achievement for a battery because to my mind, even under such abusive conditions it is still going to, on a daily basis, provide two or three years of useful service if treated daily to such harsh treatment.