CATL's CTP lithium battery technology

Over the years, a major feature of the development of the battery industry is the rapid technological iteration. On September 26, 2019, CTP technology (CELL TO PACK, no module technology) launched by CATL revolutionized the original battery assembly technology.

The head of the CTP project team of CATL said that after adopting the technology without modules, the volume utilization rate of the battery pack has been increased by 15% to 20%, the number of battery pack parts has been reduced by 40%, and the production efficiency has been increased by 50%, which will greatly reduce the power battery manufacturing costs.

The advantages don't stop there. Increasing the volume utilization rate of the battery pack will undoubtedly increase the internal space capacity of the vehicle, so that drivers and passengers no longer feel cramped; reducing intermediate links, production efficiency will also be greatly improved.

In general, in the production process of power batteries, each process is provided with a checkpoint. In the past, the production method was that the battery cells formed a module through a certain frame. The module must be tested offline by the battery test systems, and then stored and transferred. If the battery pack and the module are not in the same factory area, before the battery pack is produced, the external module of the production workshop must be re-inspected and put on-line inspection again. After removing the module, the production efficiency will be greatly improved.

The most important thing is that after adopting no module technology, the system energy density of the battery pack has been greatly improved. The person in charge said that the energy density of the non-module battery pack is 10% to 15% higher than that of the traditional battery pack. The energy density of the traditional battery pack is 180Wh/kg on average, while the energy density of the non-module battery pack can reach more than 200Wh/kg.

Although there are many advantages of moduleless power batteries, there are also technical safety concerns in the industry. However, the person in charge said that there is no need to worry about security issues, and the application of moduleless technology will also reduce security risks. He explained that in the past spontaneous combustion of electric vehicles, the cause of the fire was mostly the thermal runaway of the power battery, and the cause of the thermal runaway was that the heat generated by the power battery during the charging and discharging process could not be evacuated in time. The module-less technology can free up more space for the battery pack because it reduces the use of components in the battery pack, and the heat dissipation channel of the battery is smoother.

However, in the past many electric vehicle fire incidents, some of them were caused by the wear of the battery contact parts due to the vibration generated during the driving of the electric vehicle. The module plays the role of fixing the single battery in the battery pack. Can the fixing of the single battery be guaranteed after removing the module? The above-mentioned person in charge said that in traditional battery packs, bolts are usually used to fix the module. Each battery pack has hundreds or thousands of bolts. If any bolt is not fixed well, it may bring potential safety hazards. The non-module technology uses other methods, such as new structural glue and limit frame. Glue has a certain ability to absorb vibration, which can relatively reduce the impact of vehicle vibration.

In addition, the poor waterproof level has also caused many electric vehicle fires in my country. Can the waterproof level be guaranteed after the module-less technology is adopted? CATL CTP project team leader said that the original insulation, waterproof, thermal diffusion, heating and cooling functions of traditional battery packs have not been reduced on non-module battery packs. Instead, they have been optimized and safety performance has been further improved.