Flexible anodes, also known as cable anodes, are a new type of auxiliary anode developed and applied in recent years. They are made of conductive plastic coated over a copper core. Conductive plastic is a stable modified plastic embedded with conductive materials that enables electrical conductivity. The built-in copper core in the flexible anode serves to transmit current. Due to its resemblance to a cable, it is referred to as a cable anode, or flexible anode. This type of anode is flexible, possesses sufficient mechanical strength, and exhibits excellent chemical stability. Similar to other auxiliary anodes, flexible anodes should be applied using coke breeze backfill to create a low-resistance ground bed. The installation of flexible anodes is similar to cable burial: first, dig a trench parallel to the pipeline, fill half of the trench with coke breeze, position the flexible anode, cover it with the remaining half of the coke breeze, compact it with the original soil, and finally backfill thoroughly. Flexible anodes are primarily used for cathodic protection of buried pipelines and tank bottoms. They were originally developed to address situations where severe aging of the anti-corrosion coating on old buried pipelines leads to a significant increase in cathodic protection current, making traditional cathodic protection techniques inadequate. In many cases, completely replacing the pipeline is extremely costly. Practice has shown that the application of flexible anodes successfully resolves the challenges of cathodic protection for aging pipelines. Moreover, they can widely address some of the difficulties associated with traditional cathodic protection techniques, such as interference with external structures, implementing cathodic protection in high-resistivity environments, and distributing cathodic protection current under tank bottoms.