How to improve the energy-to-volume ratio of lithium-ion batteries structurally?

　　Our lives have been tightly tied up with lithium-ion batteries, and it is hard to believe what our lives will become if we lose such convenient and efficient energy storage batteries as lithium-ion batteries.

　　With the continuous development of lithium-ion battery technology, we have also put forward higher requirements for the performance of lithium-ion batteries: smaller, lighter, and more energy storage.

　　These demands are also driving the continuous advancement of lithium-ion battery research. One way is to try to increase the energy-to-volume ratio of lithium-ion batteries from the battery structure.

　　The only thing that can really provide capacity for lithium-ion batteries is the active material. Structurally, increasing the energy-to-volume ratio means increasing the proportion of positive and negative active materials in the lithium-ion battery.

　　For example, the 21700 battery cell that Tesla is vigorously promoting recently is to use a larger diameter cell (21mm), increase the height of the cell (70mm) to increase the proportion of active materials, reduce the proportion of inactive materials such as structural parts, and increase The energy-to-volume ratio of lithium-ion batteries reduces the cost per watt-hour.

　　In addition to increasing the diameter of lithium-ion batteries, another effective way to increase the energy density of lithium-ion batteries is to reduce the thickness of the separator.

　　Lithium-ion battery (LIB) has become the main energy storage solution in modern social life. Among them, lithium iron phosphate battery is a perfect substitute for lead-acid battery, and it is the first choice for grid-connected peak shaving, off-grid energy storage, photovoltaic energy storage, UPS, data center and other industries.