The biggest disadvantage of the 18650 lithium battery is that its size has been fixed, and it is not well positioned when installed in some notebooks or some products. Of course, this disadvantage can also be said to be an advantage. This is compared to other lithium batteries such as polymer lithium batteries. This is a disadvantage in terms of customizable and transformable size. Compared to some products with specified battery specifications, it has become an advantage.

The production of 18650 lithium batteries requires a protection circuit to prevent the battery from being overcharged and causing discharge. Of course, this is necessary for lithium batteries, which is also a common disadvantage of lithium batteries, because the materials used in lithium batteries are basically lithium cobalt oxide materials, and lithium cobalt oxide materials cannot discharge at high currents, which is safe Poor.

The 18650 lithium battery requires high production conditions. Compared with the general battery production, the 18650 lithium battery requires high production conditions, which undoubtedly increases the production cost.