Cylindrical steel shell lithium ion battery

The utility model relates to the technical field of lithium ion batteries, particularly to a cylindrical steel shell lithium ion battery which comprises a battery steel shell, a battery cell accommodated inside the battery steel shell and electrolyte solution filled into the battery cell, wherein a soft polymer material layer is uniformly coated and brushed on the surface of the battery cell. Through the adoption of the technical scheme, the battery cell can be fixed well, so that the battery cell can effectively inhibit the expansion of an anode during the practical circulating process to maintain an excellent electrochemical interface; besides, the vibration energy during the use of the battery can be absorbed, so as to facilitate alleviating hidden dangers of short circuit and electrode lug twisting off caused by the shaking in the practical transportation and vibration process of the battery cell; moreover, the soft polymer material layer can reduce the pressure and breakage to the battery cell caused by the steel shell with high rigidity, strength and hardness.