As we all know, an essential component of solar street lights is the battery. How to distinguish the types of batteries? At present, domestic power batteries are mainly divided into two factions, which are divided into lithium iron phosphate group and ternary material group according to different cathode materials. Although both are secondary batteries, they can be used repeatedly for charging and discharging, but due to the difference in materials, there is still a big difference in the performance reflected in the use level.
Ternary material or lithium iron phosphate?
The so-called lithium iron phosphate battery refers to a lithium ion battery that uses lithium iron phosphate as a positive electrode material. The characteristic of this type of battery is that it does not contain precious metal elements (such as cobalt, etc.). In actual use, lithium iron phosphate batteries have the advantages of high temperature resistance, strong safety and stability, low price, and better cycle performance.
The ternary material lithium battery refers to a lithium battery that uses lithium nickel cobalt manganate as the positive electrode material and graphite as the negative electrode material. Unlike lithium iron phosphate, the ternary lithium battery has a high voltage platform, which means that under the same volume or weight, the ternary lithium battery has a greater specific energy and specific power. In addition, ternary lithium batteries also have great advantages in terms of high-rate charging and low-temperature resistance.
The nominal voltage of iron-lithium is 3.2-3.3V, and that of manganese is 3.6-3.7V. This is the most obvious difference. Advantages of the iron-lithium system: long theoretical life, excellent theoretical resistance to overcharge and overdischarge. The advantages of the ternary system: high energy density, good low temperature performance, small size, and good discharge linearity. Disadvantages of iron-lithium: large volume, heavy weight, poor discharge linearity, and poor low-temperature performance.
Disadvantages of the ternary system: slightly poor cycle life, poor life under high temperature conditions.
Guaranteed cycle life
For family cars, the rated cycle life of ternary materials and lithium iron phosphate power batteries far exceeds the actual user's usage habits, so the service life can be completely assured.
Take the current high-capacity 18650 battery of BAK Battery as an example. After 1000 cycles of charge and discharge, the battery capacity can still be maintained at more than 90% of the original.
