When people read “lithium battery”, most think of lithium-ion rechargeable, so called secondary cells. Hence both mine and Cristobols comments/answers. Your battery will degrade in storage, certainly significantly in 15 years. How much depends on conditions. The mechanisms of lithium-ion degradation are shown here.
You might be curious about how long you can store a lithium battery before it starts to degrade. Generally, lithium batteries can be stored for up to 6 to 12 months without significant degradation, provided they are stored under the right conditions.
When the temperature range is from 35°C~40°C for LFP, the calendar life is 5-6 years. But over 45°C, the calendar life will be shortened to 1-2 years. Different cathode materials have varying calendar life properties. For example, lithium iron phosphate (LFP) batteries often have a longer calendar life than nickel-rich chemistries.
There are several strategies that manufacturers, distributors, and consumers can follow to prolong the shelf life of lithium-ion batteries: Lithium batteries should be stored in cool environments, ideally between 15°C and 25°C (59°F to 77°F), and avoid high temperatures. Store at a partial charge.
The cycle life of a lithium-ion battery refers to the number of charge and discharge cycles it can undergo before its capacity declines to a specified percentage of its original capacity, often set at 80%.
While the number of charging cycles is finite, there are several practices you can adopt to extend the lifespan of your lithium battery: Avoid extreme temperatures: Keep your devices within the recommended temperature range to prevent accelerated battery degradation.
I believe that most consumers have heard that the life of a lithium battery is "500 times", 500 times of charge and discharge, beyond this number, the battery will "end of life", many friends in order to be able to extend the battery life, every …