18650 electric core
18650 is an industry term, which refers to the cylindrical battery with a diameter of 18mm and a length of 65mm, such as Sanyo, Panasonic, Samsung, Sony, etc., which are big international manufacturers. Many domestic manufacturers are also producing and selling 18650 cells. Most of the mobile power supplies seen in the market use 18650 cells. In order to compete for the cost, they basically use products made in China, and few use 18650 cells from large imported manufacturers.
The 18650 has the capacity of 2200mAh, 2400mAh and 2600mAh. It is reported that the 18650 can achieve the maximum single node capacity of 3400mAh. The mobile power supply with 18650 electric cells is basically realized by paralleling the above specifications. The 18,650 is generally packed in cylindrical steel shell, and the lithium ion inside is liquid. Because it is already an industry standard specification, the 18,650 can only be cylindrical. If you see a thick and large shape when buying a mobile power supply, you can basically determine that the 18,650 cell is used.
Speaking of safety, batteries are energy bodies. In extreme cases, serious accidents may occur in XXXX Co., Ltd. The 18650 battery cell is packed in steel shell, which will explode in the most serious case. For example, the 18650 battery cell is used by the notebook battery that we are familiar with. In the early years, Sony Corporation recalled the battery in batches due to a serious accident of XXXX Co., Ltd.
By 2014, many mobile power supplies in the market had adopted low-quality 18650 cells in order to reduce costs and fight for low prices, which made it impossible to defend against people. Mobile power is a product that users carry with them. If XXX Co., Ltd. fails to pass the test, it will be like walking around with a time bomb. Therefore, when purchasing products, we should comprehensively measure the brand and price of products and not just pursue the cheapest.
Polymer core
The polymer cell is generally made of lithium cobalate, lithium manganate and ternary lithium. The outer packaging is mainly made of aluminum plastic film, and the lithium material in the middle is paste, so the shape can be customized at will. For example, an ultra-thin battery such as 0.25mm can be used. Therefore, the mobile power supply using the polymer cell can be designed more flexibly in appearance. For example, some ultra-thin mobile power supplies on the market, as well as the back clip of the iPhone 4, use polymer power cells.
Electric core capacity dividing equipment (i.e. electric core capacity detector) (2 pieces)
The polymer battery is flexible in packaging. Unlike the 18650, it has a fixed size. Its capacity directly depends on the size of the volume and the raw materials used.
For polymer cell, the biggest potential safety hazard is liquid leakage and short circuit, which will lead to bulge, and combustion in the worst case. Compared with 18650, the safety of polymer core is relatively better. However, combustion will also bring potential safety hazards, so it is recommended that users who use mobile power should not place the mobile power supply in a flammable environment.
In 2014, the mobile power supply with 18650 cells was still used in the market, and most products of Pinsheng and other brands used 18650 cells, while most high-end mobile power supplies used polymer cells. From the perspective of safety, it is recommended that users consider the use of polymer core products as much as possible when purchasing mobile power supplies, especially mobile power supplies with large capacity, such as more than 8000mAh. If multiple 18650 cores are connected in parallel, the explosion is very terrible, while the polymer core will never explode, and at most it will generate flames.