Why is there such a big difference in the price of each brand of lithium-ion batteries on the market, and what factors determine the price of high and low.
1, the selection of electric cells.
First, the selection of different material system cells will affect the overall lithium-ion battery price. Lithium-ion battery according to the different cathode materials, there will be lithium manganate (3.6V), lithium cobaltate (3.7V/3.8V), lithium nickel cobalt manganate (commonly known as ternary, 3.6V), lithium iron phosphate (3.2V), lithium titanate (2.3V/2.4V) and other materials system of the cell, its different materials system of the cell, its voltage platform, safety factor, cycle times, energy density ratio, the Working temperature, etc. are different.
Secondly, the price of different brands of battery cells will also vary greatly, the total price gradient can be divided into: special battery cells (including ultra-low temperature, ultra-high temperature, ultra-high rate, shaped), Japan (Panasonic, Sanyo, Sony), South Korea (Samsung, LG), China (Lixin, BAK, BYD, ATL), the same material system and different brands of battery cells, the price difference will also be very large, and through the market superiority and inferiority The quality (safety, consistency, stability) of each brand of battery cells is basically proportional to the price.
2, the demand and design of lithium-ion battery PCM
PCM design can be divided into: basic protection, communication, BMS
Basic protection: Basic protection includes overcharge, overdischarge, overcurrent and short-circuit protection, and over-temperature protection can be added according to product requirements
Communication: Communication protocol can be divided into I2C, RS485, RS232, CANBUS, HDQ, SMBUS, etc. There is also a simple power display, which can be used to add power meter using LED indication.
Battery Management System: BMS is the combination of the first letter of BATTERY MANAGEMENT SYSTEM, called the battery management system, commonly known as the battery nanny or battery housekeeper, is important in order to intelligent management and maintenance of each battery cell, to prevent the battery from overcharging and over discharging, prolonging the life of the battery, monitoring the state of the battery. Its important functions include: real-time monitoring of battery physical parameters; battery status estimation; online diagnosis and early warning; charging, discharging and pre-charging control; equalization management and thermal management, etc. Subsystems are mostly applied to electric vehicle batteries.
3, the needs and design of lithium-ion battery shell
Lithium-ion battery shell design can be divided into: PVC heat sealing, plastic, metal
PVC heat sealing: the specific external battery pack using what kind of shell packaging form, it is important to depend on the specific needs of the guests of the product, on the use of PVC heat sealing packaging form, generally applicable to the cell string and the number of lighter overall weight (≤ 2kg), can be used. But about the overall weight of ≥ 1kg battery pack, to add fixed bracket between the cells, the periphery of the glass fiber plate protection, and then use PVC heat sealing.
Plastic: the use of plastic shell, it is important that different battery packs after shaping, involving the shell may have to open the mold, mold costs are a considerable expense, such as the development of the early stage, the product has not been shaped, you can use the hand shell prototype (hand strength is not as strong as the material strength after shaping the mold), the shell of the material and process (especially with three anti) requirements are different, will also affect the cost.
Metal: metal shell is also the same as the plastic shell, the product is not finalized before or the number of demand is not much, it is recommended to use sheet metal prototype, so that the important thing is to make samples with a shorter delivery time, such as batch is larger, it is also recommended to open the mold. About the metal shell has a waterproof level requirements, will also greatly affect the cost, there are special materials (such as titanium, etc.) metal shell requirements, the cost will be higher.
