Since the summer of 2020, we have begun to hear about the 4680 battery cell and CTC battery solutions. We waited for 2 years when these two technologies were truly applied. Tesla Model Y uses Tesla's self-developed 4680 battery cell, using CTC technology; BYD also uses CTB batter

Since the summer of 2020, we have begun to hear about the 4680 battery cell and CTC battery solutions. When the two technologies of

were truly applied, we waited for 2 years. Tesla Model Y uses Tesla 's self-developed 4680 battery cell, using CTC technology; BYD also uses CTB battery technology, which is also a type of CTC. When the two electric vehicle giants were unable to break through the bottleneck of battery formula, they began to make efforts in mechanisms and utilization.

After Tesla's 4680 battery cell was launched, the density was higher than the battery provided by the original supplier, which increased the vehicle's battery life by 16%. At the same time, only 950 battery cells are needed, which can achieve an energy density of 330Wh/kg.

Electric vehicles pursue range for a higher range by using batteries with higher energy density to obtain high range. When the formula cannot be broken through, you can only insert more battery cells into the battery pack to improve battery life. Each next battery pack similar to CTC technology should have this original intention.

But if all use battery technology similar to CTC, if there is an accident in the vehicle, the battery may really be ineffective? When you turn on Tesla with

, can the battery be replaced?

The recently delivered models of Tesla Model Y in the US market have begun to use 4680 batteries, and this CTC battery pack may also be used on Tesla models made in China in the future. This kind of battery has its advantages and disadvantages. Although it has greatly changed its energy density and battery life, after the collision, it is not as difficult as changing to a new battery directly.

First talk about the advantages of this type of technology. The Tesla Model Y equipped with 4680 batteries directly makes the battery pack into the bottom of the car, and the seat is directly arranged and installed above the battery pack. There are only a few beams that separate the seat from the battery. Then, under the premise that the total weight of the battery is only within 500 kg, the energy density reaches 80kWh.

is light and has a high density.

However, we must also admit that the design of 4680 battery cell and CTC technology is indeed the most advanced at present; even if it is advanced, it is still in the early stage of development, and there are still immature areas, such as maintenance.

Why is Tesla's CTC not recommended to fix it?

After disassembling the CTC battery pack used by Tesla, the inside is covered with a large amount of polyurethane foam glue. The amount can no longer be considered filling, but is exaggerated to the extent that each battery cell of the bag is tightly wrapped together. The characteristics of this material include softness, flame retardant, thermal insulation, sound insulation and shock absorption, and its chemical properties are relatively stable, so the service cycle is relatively long.

Tesla's purpose of using this material is not difficult to understand:

1. In order to fix the battery cell, it replaces the fixed bracket in a conventional battery pack, further improving the energy density;

2. Provide isolation and buffering between the battery cells, which has a positive effect in improving the stability and collision safety under bumping and vibration conditions;

3. The material has good thermal insulation performance, effectively reducing the impact between the battery cells and the impact of the external environment on the battery itself.

Similarly, this is one of the reasons why Tesla's CTC battery is difficult to repair.

According to normal logic, the collision causes damage to the battery pack. Unlock the bottom shell of the battery pack, remove the entire layer of the filling material with very high viscosity, and then replace it with a single or multiple battery cells. Then, the filling material must be re-covered in the battery pack. It has no repairability and is also a "nightmare" for the battery recycling industry.

or above should be the process of replacing and repairing a single cell or multiple battery cells. If you switch to Tesla's CTC and use the same operating procedure to repair the battery, the cost should be enough to replace a new battery. Does

use CTC or similar batteries? It cannot be repaired?

has no possibility of repair, is it a common problem with CTC-type batteries?

Nowadays, the CTC battery technology is used in China, including Zero-Pony CTC battery chassis integrated technology and BYD CTB battery body integrated technology. There are only these two options available at present, and there may be "CTC" batteries launched by suppliers such as CATL in the future. No matter how they are named, the underlying technology type they use is CTC.

So can this type of CTC product be repaired? The use of the CTC battery structure of

Zero Run is the floor panel and the upper shell of the ground pool into one. The battery structure is divided into two parts: the upper shell and the battery body. Then, the entire vehicle and the battery pack are sealed through sealant. In this way, maintenance convenience may be better than Tesla's CTC battery, after all, it is not a structure that is directly embedded under the seat.

However, convenience is just to remove the battery pack from the body, this link. The inside of the battery is also directly intercepted by a battery cell. Without the saying of the battery module, the inside should also be wrapped with filling materials, but it is unknown what it is used, but it must meet the necessary conditions such as shock absorption, stability, strong adhesion, and fire prevention.

Similarly, BYD's CTB is the same. The upper and lower layers of adhesive are directly encapsulated around the battery cell, which is enough to minimize the possibility of maintenance; and BYD's blade battery cell also plays a role in strengthening the beam in the CTB battery system, and if an accident occurs, the battery cell will also be subjected to stress.

So whether it is damage to a single battery cell or damage to multiple battery cells caused by a collision accident; from the perspective of repair steps, repairing may be more expensive than replacing the battery.

Let me say that the above mentioned above are all the initial products of technology, which are iterated from CTP. The most advanced technology is currently available, but it has not experienced technical iteration, so there are still immature points. Next, there are also solid and semi-solid state batteries that need to be considered for maintenance convenience. How to repair a single battery cell or a damaged battery pack? Repair or replace? These are all problems, and they are generally unsolvable in the early stages of the product.

For electric car , can you really afford to buy it and repair it?

For most of us ordinary consumers, the probability of encountering accidents that damage the chassis or batteries should not be very high; unless it is a major or serious traffic accident, the general battery will not need to be repaired and you can change the car directly. Look at this matter rationally. More safety beams will be added to the electric vehicle chassis, especially around the battery, including longitudinal beams and cross beams to ensure that the battery can remain stable, safe and not catch fire after a collision.

The development of things, technological progress will inevitably be accompanied by two sides. In addition to batteries, most high-end electric vehicles will soon embark on the road of integrated die-casting. Like the previous Tesla Model Y integrated die-casting repair cost of about 200,000 yuan. If the battery repair cost is added, it may be more cost-effective to change the car directly.