Most LiFeP04 batteries can be discharged 95%, but 80% is recommended to maximize battery life. A 200Ah lithium phosphate (LiFeP04) batteryconnected to a 400 watt DC load with 80% Depth of Discharge will last for almost 5 hours. A 200Ah lithium phosphate (LiFeP04) will run a 400W rated fridge for about 55 hours at a rate of 40 watts per hour.
@Moab: I should have been more clear in my previous post. The CR2032 is not a lithium-ion battery. It's simply called a lithium battery because it uses lithium metal or lithium compounds in the anode. See this wikipedia page for details. – Battery degrades by 10% and 23% at 1.2C and 1.5C respectively at the end of 300 cycles as against degradation by 7% at 1C. Increased charging rates negatively affect the lifetime. Charging at rates higher than 4C alters the chemical composition resulting in significant damage and reduction of life. My understanding, from being an electric vehicle owner, is that routinely limiting the charge to 70-80% is the best way to maximize the battery pack's life span. Charging to 100% is only done when anticipating a long trip. Is this not the case for all rechargeable Li ion batteries, from cell phones and laptops to portable tools and appliances? Researchers demonstrate a solution to a 40-year problem. Researchers have designed a stable, lithium-metal solid state battery that can be charged and discharged at least 10,000 times -- far more 6DB7UK.