Li-ion battery packs are not sensitive to temperatures in the range of 0-40℃, however, once the temperature exceeds this range, the life and capacity will be reduced. The low-temperature performance of lithium-ion batteries is also different for different materials.
Temperature range of ternary lithium-ion battery packs
Conventional ternary lithium-ion battery pack operating temperature: -20 ℃ ~ 60 ℃, but generally lower than 0 ℃ after the lithium-ion battery performance will decline, the discharge capacity will be reduced accordingly, so the lithium-ion battery performance of the full operating temperature, common is 0 ~ 40 ℃. Some special environmental requirements of the lithium-ion battery temperature is different, some can even be in the hundreds of degrees Celsius in the normal operation of the environment.
The operating temperature of ternary lithium-ion batteries is generally 0-40 degrees. For lithium-ion battery packs, the industry has not yet had a clear theory to support its internal resistance, discharge platform, life, capacity and other inevitable link between the performance of each temperature, the relevant formula and mathematical model is still in the groping stage. By and large, lithium-ion batteries are not sensitive to the temperature in the interval 0-40 ℃, however, once the temperature exceeds this interval, life and capacity will be discounted.
Exhaustive non-quantitative currently there is no method, because the lithium-ion battery pack activity is too high, consistency is also the biggest problem, even if the same batch, the same material, the same process of the product, the performance will be very different. Therefore, ternary lithium-ion batteries in the winter time is necessarily shorter than the summer.
As a rechargeable lithium-ion battery, ternary lithium-ion battery pack output voltage stability, high output voltage, stable performance, large capacity, long service life, a wide range of operating temperatures, good safety and environmental protection and pollution-free, so in the future lithium-ion batteries on the road to development has a lot of upward space.
Ternary lithium-ion battery pack system cooling methods
Ternary lithium-ion battery pack heat dissipation has active and passive two kinds, there is a big difference in efficiency between the two. The passive system requires a relatively low cost, and the measures taken are simpler. The active system is relatively more complex and requires more additional power, but it is more effective in thermal management.
◆ Power ternary lithium-ion battery pack air-cooled structure heat dissipation method
1、A cooling fan is installed at one end of the ternary lithium-ion battery pack, and ventilation holes are left at the other end to accelerate the flow of air between the gaps of the battery cell, and take away the high heat that springs up when the battery cell is working;
2. Add heat-conducting silicone spacer at the top and bottom of the battery pole, so that the heat that is not easy to be emitted at the top and bottom can be conducted to the metal shell through the TIF heat-conducting silicone sheet to dissipate the heat, and at the same time, the silicone sheet's high electrical insulation and puncture-proof performance has a very good protective effect on the battery pack.
◆Power lithium-ion battery pack liquid cooling structure heat dissipation method
1, the heat of the electric cell is transferred to the liquid cooling tube through the thermally conductive silicone film, and the heat is taken away by the free circulation flow of the coolant by thermal expansion and contraction, so as to make the temperature of the whole battery pack uniform, and the strong specific heat capacity of the coolant absorbs the heat generated by the electric cell when it is working, so as to make the whole battery pack operate within the safe temperature.
2, thermal conductive silicone sheet good insulation properties and high resilience toughness, can effectively avoid the vibration friction between the battery cell breakage problems, and short-circuit potential danger between the battery cell, is the best water-cooled program of auxiliary materials.
Natural convection heat dissipation of power battery packs
1, this kind of ternary lithium-ion battery pack space, good contact with the air, the exposed part can be through the air natural heat exchange, the bottom can not be natural heat exchange parts of the heat dissipation through the radiator, thermal conductive silicone film filling the gap between the radiator and the battery pack, thermal conductivity, shock absorption, insulation.
2, the heating pad program is mostly used in the new energy vehicle market, before starting the battery preheating heating pad heat through the thermal conductive silicone film will be transferred to the lithium-ion battery pack, preheat the battery, thermal conductive silicone film has a good thermal conductivity, insulation, abrasion-resistant performance, effective heat transfer and protection of ternary lithium-ion battery packs and heating pads between the friction of the emergence of wear and short-circuit, and so on.
One of the major disadvantages of ternary lithium-ion battery is the impact and high temperature when the ignition point is low. Therefore, the protection of lithium-ion battery is very high to prevent accidents. Lithium-ion batteries, as the energy source of electric vehicles, are the most critical components of electric vehicles, which directly affect the performance of electric vehicles. The temperature is one of the key factors affecting the performance of the battery pack, the battery in the work of sprouting a large amount of heat due to the influence of the space and the accumulation, resulting in the temperature imbalance of the battery pack in various places, thus affecting the consistency of the battery pack monomer battery.
Therefore, in order to let the ternary battery pack in the most suitable working condition, play the best performance and life of lithium-ion battery pack, to the battery heat dissipation is particularly important.
