Lithium battery price composition and price influencing factors
Lithium battery price composition
The price of lithium battery is mainly composed of three parts: battery core, protection board, and shell. At the same time, due to the power consumption and current of electrical appliances The size of the connecting piece between the batteries (conventional nickel piece, molded nickel piece, copper-nickel composite piece, jumper piece, etc.) will affect the cost, different connectors (such as aviation plugs, from ten A few yuan to thousands of yuan) may have a greater impact on the cost, and different PACK processes will also affect the cost.
Influencing factors of lithium battery price
1. Selection of battery cells
First, the selection of cells with different material systems will affect the price of the entire lithium battery. According to different cathode materials, lithium batteries will have lithium manganese oxide (3.6V), lithium cobalt oxide (3.7V/3.8V), lithium nickel cobalt manganese oxide (commonly known as ternary, 3.6V), and lithium iron phosphate (3.2V) , Lithium titanate (2.3V/2.4V) and other battery cells with different material systems, their voltage platform, safety factor, cycle times, energy density ratio, working temperature, etc. are different.
Second, the prices of batteries of different brands will vary greatly. The total price gradient can be divided into: special batteries (including ultra-low temperature, ultra-high temperature, and ultra-high rate). , Heterogeneous), Japanese (Panasonic, Sanyo, Sony), Korean (Samsung, LG), domestic (domestic is divided into first-tier (Lishen, Bick, BYD, ATL), second-tier, and even five-tier, six-tier Line), the price difference of batteries of the same material system but different brands will be very large, and the quality (safety, consistency, stability) of the batteries of each brand through the survival of the fittest in the market is basically proportional to the price of.
2. Requirements and design of lithium battery PCM
PCM design can be divided into: basic protection, communication, BMS< /p>
Basic protection: basic protection includes over-charge, over-discharge, over-current and short-circuit protection. Over-temperature protection can be added according to product requirements.
Communication: The communication protocol can be divided into I2C, RS485, RS232, CANBUS, HDQ, SMBUS, etc. There is also a simple power display, which can be indicated by a power meter and LED.
BMS: BMS is the first letter abbreviation combination of BATTERYMANAGEMENTSYSTEM, called battery management system, commonly known as battery nanny or battery housekeeper, mainly for intelligent management and Maintain each battery unit, prevent the battery from overcharging and over-discharging, prolong the service life of the battery, and monitor the status of the battery. Its main functions include: real-time monitoring of battery physical parameters; battery state estimation; online diagnosis and early warning; charge, discharge and precharge control; balance management and thermal management, etc. The secondary system is mostly used in electric vehicle batteries.
3. Requirements and design of lithium battery shell
The design of lithium battery shell can be divided into: PVC heat sealing, plastic , Metal
PVC heat sealing: What kind of shell packaging is used outside the battery pack depends mainly on the specific needs of the customer’s product. For the packaging using PVC heat sealing It is generally applicable when the number of batteries in series and parallel is small and the overall weight is light (≤2kg). However, for battery packs with an overall weight of ≥1kg, it is necessary to add a fixing bracket between the cells, and to protect the periphery with a glass fiber board, and then use PVC heat sealing.
Plastic: plastic shell is used, mainly after different battery packs are shaped, the shell involved may need to be molded, and the mold cost is a considerable expense, such as In the early stage of development, the product has not been finalized, and the prototype shell can be used for proofing (the strength of the prototype is not as good as the strength of the material after the mold is opened and shaped). Different requirements for the material and process of the shell (especially with three-proof requirements) will also affect the cost.
Metal: The metal shell is also the same as the plastic shell. Before the product is finalized or the quantity demand is not large, it is recommended to use sheet metal sample preparation, which is mainly because the sample preparation and delivery time are short , If the batch is large, it is also recommended to open the mold. The requirements for the waterproof level of the metal casing will also greatly affect the cost, and the cost will be higher if the metal casing is required for special materials (such as titanium alloy, etc.).
The cost of lithium batteries is mainly composed of batteries, PCM, and structural parts. In addition, the company's PACK costs, aging costs, and management costs must be added. At the same time, due to the different requirements of product technical difficulty, purchase amount, and defective rate, the price of lithium batteries will vary greatly!