4680 Battery Disassembled, Tesla Secrets Finally Revealed

Youtuber @The Limiting Factor brings you a teardown and analysis of Tesla's latest 4680 battery, giving some specs on the unique design of this battery.

The Model Y from the Texas plant is the most advanced product in Tesla's portfolio today. It uses three cutting-edge technologies: CTC technology (a technology that mounts cells directly to the chassis), 4680 cells and one-piece die-casting, which significantly reduces the difficulty and cost of assembling the vehicle and improves performance.

The cathode of the Tesla 4680 battery is described as using NCM811 material, while the anode is graphite.

The video shows that Tesla's in-house production 4680 battery (about 6 months old) is equipped with NCM 811 cathode chemicals and has 81.6% nickel in the material, while the cobalt and manganese content has not been disclosed, but there appears to be no aluminum (so no NCA or NCMA).

The Limiting Factor notes that the new dry cell electrode technology has not yet been used for the cathode, but it is currently being used for the anode, and it is expected that it will work or not work in both cases.

The analysis found that there is no silicon in the 4680 cell anode material and that the anode active material is graphite. It is known that battery manufacturers typically add 10-15% silicon to the most advanced lithium-ion battery anodes to increase energy density. At this point, the media believes that this early 4680 battery may be different from the current chemical electrode technology used by Tesla.

Nevertheless, data analysis shows that the battery features are very good, such as energy density of 272- 296Wh/kg.

The Tesla 4680 battery is said to weigh 355 grams and has an estimated total capacity of 26.136 Ah, while the total energy is estimated at 96-99 Wh (assuming 3.7-3.8 V), which is in line with the 98 Wh rumor.

The media pointed out that the energy density of 4680 battery is about 272-296 Wh/kg range, which is very good among the batteries currently on the market and basically belongs to the first tier of performance.

For reference, next year's mass production of Ningde CTP3.0 Kirin battery integration is a global high, volume utilization rate exceeds 72%, energy density can reach 255Wh/kg, claiming that the vehicle can easily achieve a range of 1000 km. Of course, Ningde Time's advantage is the world's first large surface cooling technology of the battery cell, Kirin battery can support 5 minutes fast hot start and 10 minutes fast charging.

A brief summary:

4680 type cylindrical lithium-ion battery (diameter 46mm, height 80mm, weight 355g)

Cathode: NCM 811 (81.6% nickel)

Anode: Graphite (silicon free), dry cell electrode technology

tabless design

Estimated total capacity: 26.136 Ah

Estimated total energy: 96-99 Wh (assumed at 3.7-3.8 V)

Estimated energy density: 272-296 Wh/kg

Troy Teslike noted that there are rumors that Tesla's first-generation battery is 98 Wh. Higher energy density models will be introduced in the next few years: 108 Wh in 2023 (up 10%) and 118 Wh in 2024 (up another 9.3%).

The 4680 cell is already said to store more than 5 times more energy than the smaller 2170 cell. Taking into account the rumored total energy content, the energy density is

First generation: 276 Wh/kg

Second generation: 305 Wh/kg

Third generation: 333 Wh/kg

However, it was also noted in April that the Type 4680 battery may be available in two pack configurations.

Standard: 690 cells (69 x 10) and 67.620 kWh (98 Wh/cell)

Long range: 828 cells (69 x 12) and 81.144 kWh (98 Wh / cell)
Of course, the 4680 Model Y is not currently listed as a long-range version in EPA documents, but only as AWD, and its range is not much better than the version with the 2170 battery (279 vs. 330 miles).

In addition, the new battery has a much thicker steel case (battery skin) than the 2170. The media believes that the reason behind this is probably because the new battery pack structure requires a stronger load-bearing capacity. As a result, it makes the 4680 battery heavier. According to the video, this part of the weight loss is estimated at 10-15%.

Model 2170: 125-250 microns

Type 4680: 500-600 microns

But as we saw above, despite this, the energy density of the two is comparable

Type 2170: 263-276 Wh/kg

Type 4680: 272-296 Wh/kg

Although the potential of the 4680 battery is currently untapped, the fact that it has a structural battery design means that Tesla will be able to further reduce weight at the structural level of the car, allowing for significantly higher energy density at the car level. At least, that's what Musk said in 2018.

The video shows that the new cell may have such a competitive energy density (despite the heavy can and the absence of silicon anodes) due to the thickness of the electrodes (more active material).

In the case of the new cell, the cathode thickness seems to be 20-25% higher:.

Type 2170 (typical): 60-70 microns (0.06-0.07 mm)

Type 4680: 85 microns (0.085 mm)