Is a Cylindrical Cell Battery the Best Lithium-ion Battery Type?
What is a cylindrical cell battery?
Cylindrical lithium batteries are divided into lithium iron phosphate, lithium cobalt oxide, lithium manganese oxide, cobalt manganese hybrid, ternary materials and other systems. The shell has two kinds: steel shell and polymer . Different material systems have different advantages. Generally, the cylinder is for the steel shell cylindrical cell battery and lithium iron phosphat, Because of its high output voltage, large capacity, good charge and discharge cycle performance, stable output voltage, discharge current, electrochemical characteristics of stable performance, safe use, wide working temperature range, environmental protection, which is widely used in solar energy lamps, lawn lamps and lanterns, alternate energy sources, electric tools, toys.
Cylindrical cell battery structure
Typical cylindrical cell battery structure includes: case, cover, positive, negative, diaphragm, electrolyte, PTC element, gasket, safety valve, etc. Generally, the battery case is the negative electrode of the battery, which is made of nickel-plated steel plate, and the cap is the positive electrode of the battery.
The advantages of cylindrical lithium batteries
Compared with soft packs and square lithium batteries, cylindrical lithium batteries have the longest development time, high standardization, mature technology, high yield, and low cost.
·The production technology is mature, the cost of PACK is low, the yield of battery products is high, and the heat dissipation performance is good.
The cylinder has a large specific surface area and good heat dissipation effect.
·Cylindrical batteries are generally sealed and there is no maintenance problem during use. The battery shell can withstand high voltage, and there will be no swelling of square and soft-packed batteries during use.
Cylindrical cell battery cathode material
At present, the mainstream commercial cylindrical battery cathode materials mainly include lithium cobalt oxide (LiCoO2), lithium manganese oxide (LiMn2O4), ternary (NMC), lithium iron phosphate (LiFePO4), etc., and batteries with different material systems have different Features.
Anode material for cylindrical cell battery
Cylindrical battery anode materials are roughly divided into six types: carbon anode materials, alloy anode materials, tin-based anode materials, lithium-containing transition metal nitride anode materials, nano-level materials, and nano-anode materials.
Cylindrical lithium battery cells
Brands of cylindrical lithium ion batteries
Cylindrical lithium-ion batteries are more popular among Japan and South Korea Lithium-ion companies. There are also large companies producing cylindrical lithium batteries in China.The earliest cylindrical lithium battery was invented in 1992 by Japan’s SONY company. Well-known cylindrical lithium-ion battery brands: Sony, Panasonic, Sanyo, Samsung, LG, Wanxiang A123, BAK, Lishen, etc.
Types of cylindrical lithium ion batteries
Cylindrical lithium-ion batteries are usually represented by five digits. Counting from the left, the first and second digits refer to the diameter of the battery, the third and fourth digits refer to the height of the battery, and the fifth digit denotes the circle. There are many types of cylindrical lithium batteries, the more common ones are 10400, 14500, 16340, 18650, 21700, 26650, 32650 and so on.
The 18650 battery is a lithium battery with a diameter of 18mm and a height of 65mm. Its biggest feature is its very high energy density, almost reaching 170 Wh/kg. Therefore, the battery is a relatively cost-effective. Most of the batteries we usually use are 18650 battery, because it is a relatively mature and the system quality is stable in all aspects.
Comparison of cylindrical lithium battery and soft pack lithium battery
The safety performance of the soft pack battery is better than that of cylindrical lithium batteries.. It is structured with aluminum-plastic film packaging. When safety issue occurs, the soft pack battery will generally expand and crack, rather than explode like a steel shell or aluminum shell battery.
The weight of the soft pack battery is relatively light, around 40% lighter than the steel shell lithium battery of the same capacity, and 20% lighter than the cylindrical aluminum shell lithium battery; the internal resistance of the soft pack battery is smaller than that of the lithium battery , which can greatly reduce the self-consumption of the battery;
The cycle performance of the soft-pack battery is good and longer, and the attenuation of 100 cycles is 4% to 7% less than that of the cylindrical aluminum shell battery;
The design of the soft pack battery is more flexible, the shape can be changed to any shape, and it can be thinner. Also, it can be customized according to customer needs,thus new battery cell models can be developed. While the cylindrical lithium battery does not have this condition.
Compared with the cylindrical lithium battery, the disadvantages of the soft pack battery are poor consistency, easy leakage and higher cost,. However, high cost can be solved by large-scale production, and improving the quality of aluminum plastic film can solve the problem of liquid leakage.
In conclusion, the technological progress of cylindrical cell battery mainly comes from the development of innovative research and application of key battery materials. The type of cylindrical battery is a not bad choice for Lithium-ion battery.