LFP (LiFePO4) Batteries: The effect of discharge rate and depth of discharge on battery life

I think that, for quite a lot of folks, battery life is a major consideration. I have posted this graph about lithium ferro-phosphate (LiFePO4) battery life elsewhere, so apologies if you find this repetitive. The graph is from a particular manufacturer, but it is likely to be broadly representative of any brand.

You can read the graph for yourself but, broadly speaking, what it is saying is that (for the right-hand half of the graph where most of us will be operating) discharging at 1/2C instead of 1C could reasonably be expected to increase your battery life by something in the region of 40%.

Reducing DOD from 100% to 90% could increase the life by about one sixth. Going from 100% DOD to 80% DOD increases it by about one half. Going from 100% DOD to 70% DOD roughly doubles it.

I would guess that other factors, such as temperature, would have significant effects on battery life.

Some users will be less cost-sensitive than others. I imagine that a business in South Africa, where "load shedding" happens every day, would be more concerned with keeping their computers running than eking out the most cycles from their batteries. A domestic user in the UK like me will be more likely to want to put off replacing their batteries.

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