Tesla CEO Elon Musk wants to extend the lifespan of electric car batteries to 1.6 million kilometers, and a new patent filed by the company confirms that Tesla is accelerating towards this goal.

The new patent describes a method and process for synthesizing nickel-cobalt aluminum (NCA) electrodes for the new battery lithium manufacturing process, which can significantly improve battery life while also reducing battery manufacturing costs.

Currently, Tesla has been filing U.S. and international patents on the new technology. According to the latest news, Tesla has passed an international patent application for the battery technology through Tesla Canada.

Tesla's development of ultra-long-life batteries is no secret

This time with the revelation of Tesla's new battery patent, information has come out since last year that Tesla is working on an ultra-long-life battery.

In 2019, JeffDahn, Tesla's Battery Research Directions partner, published a new paper on batteries, which mentions that the batteries being developed in collaboration with Tesla have a range of more than 1.6 million kilometers, and that the new batteries can sustain 4,000 charge-discharge cycles at extreme temperatures of minus 40 degrees.

Also in 2019, Tesla has made a lot of moves in the battery space, announcing the $218 million acquisition of Maxwell Battery Company for a 55% premium, a secret research center for its own batteries, and university collaborations on new battery technology.

This time, Tesla filed a new patent titled "Nickel-Cobalt Aluminum (NCA) Electrode Synthesis Method," which describes a new, highly efficient new electrode synthesis method for battery production called the Nickel-Cobalt Aluminum Electrode Heating Process.

Previous heating methods have sometimes resulted in the formation of impurities called lithium substrates (L15AIO4), and lowering the lithium content in the battery, while reducing contamination, can also result in poorer electrochemical performance.

For this phenomenon also mentioned in the new patent, the battery will be heated to a temperature sufficient for the growth of a single crystal. The corrected ratio of lithium to other metals will limit the formation of impurities during the first heating. The lithium will be heated a second time at a lower temperature than the first heating cycle.

According to researchers involved in the patent, this process has helped to develop impurity-free single-crystal NCAs that can reach more than 4,000 charge-discharge cycles, resulting in a battery life of up to 1.6 million kilometers.

At this stage, the battery life of the Tesla model is far less than 1.6 million kilometers, when the vehicle was designed with the 1.6-million-kilometer target in mind.

The current body structure, electric drive and electronic system life are all achievable, but the battery is certainly the short end of the stick. The current Tesla power battery life is only around 500,000 km.

The introduction of Tesla's 1.6 million kilometer-life battery will be a revolutionary innovation and a great achievement for the automotive battery industry.

The most durable lithium iron phosphate battery is only about 2,000 times, and the future Tesla's new battery, which can be charged and discharged more than 4,000 times, will undoubtedly have an overwhelming advantage after its introduction.

However, the fact that the new battery has been fitted to all Tesla models does not mean that the car will be able to drive 1.6 million kilometres, as the life of the car depends on a number of factors, including the quality of the parts, manufacturing and craftsmanship of the vehicle.

Internal combustion engine vehicles have been around for more than 100 years, and it's not uncommon to see more than 1 million kilometres in your life.

Internal combustion engine technology is now very well established, with low production costs and high serviceability.

The development of long-lasting batteries is an urgent problem, and the development of long-lasting batteries is also a big industry trend.

Two types of mainstream batteries for new energy vehicles in China

At present, China's new energy vehicle field is most used in the two types of lithium iron phosphate and lithium ternary batteries.

Lithium-ion batteries using lithium iron phosphate acid as the cathode material. (Lithium-ion battery cathode materials are mainly lithium cobaltate, lithium manganate, lithium nickelate, ternary materials and lithium iron phosphate).

Advantages.

Low cost and cheap.

Safe and stable: high temperature resistance, non-flammable.

Stability is the best of the current automotive batteries, and the number of charges and discharges around 2000, as mentioned earlier, is also the highest of the current battery types.

Weaknesses.

The energy density is still not a small gap compared to the ternary lithium battery, lithium cobaltate.

Larger and heavier, they take up a lot of space in the vehicle when loaded and force the entire vehicle to weigh more.

Too low a temperature can seriously affect the service life, and models for lithium iron phosphate applications are not suitable for use in cold areas of northern China.

Li-ion battery is a lithium battery with lithium nickel-cobalt-manganese ternary anode material.

Advantages.

Small size, high energy density, high power storage capacity (preferred battery solution for high-end trams)

It can adapt to cold weather better, charge and discharge at low temperature, and the battery is more stable.

Weaknesses.

The low cycling life is a costly addition to vehicle use.

The cost is higher (although after two years of upgrading the size of the Li-ion battery, manufacturing costs have fallen significantly and are still on the high side for low-priced models).

Poor stability, high energy density ratio of ternary lithium, safety and stability is necessarily lower than that of lithium iron phosphate acid (and the chemical reaction of ternary lithium material is particularly strong, 50-300 ℃ high temperature will produce decomposition, once the release of oxygen molecules, under the action of high temperature electrolyte burned quickly, and then the phenomenon of explosion combustion).

Graphene batteries have been noisy in recent years, and in experiments, they can compress hours of charging time to less than a minute.

Adding graphene to the lithium battery can help the lithium battery to reduce the heat during production capacity, minimizing energy loss, avoiding a lot of energy being wasted, reducing heat damage to the battery and improving battery life.

Graphene batteries, also known as "pure gold" battery, add graphene to the lithium battery, production cost is too expensive, about 2,000 yuan per gram, simply can not be used on a large scale, graphene batteries at this stage is only used in the aerospace industry, which does not count the cost.

Graphene batteries for new energy vehicles are still in the experimental stage, and none of the mass-produced models are yet equipped.

The current lithium iron phosphate battery has been widely used in the electric vehicle industry, except for small new energy vehicles, like electric buses and other heavy vehicles are using lithium iron phosphate battery.

The rapid development of Li-ion battery in China over the years cannot be separated from China's new energy subsidy policy in the past few years, and the state has favored models with long range and high energy density of the battery system in the past few years, so many car companies' products are close to the Li-ion battery.

But when the subsidies receded, many low-priced and mainly cost-effective models had to reconsider the use of lower-cost lithium iron phosphate batteries.

Why is Tesla developing ultra-long-life batteries?

Tesla currently uses a single 18650 as well as the latest 21700 batteries, both of which now fall well short of the 1.6 million kilometers of life mentioned in Tesla's new patent.

On January 4, 2017, Tesla announced the start of mass production of the new 21700 battery, developed in conjunction with Panasonic.

With the 21700 battery in use, Tesla officials also say the 21700 battery is 20 percent more energy dense than the 18650 battery, with system costs expected to drop by about 9 percent and weight by about 10 percent.

The batteries currently used in the Tesla Model 3 are manufactured and supplied by two companies, Panasonic and LG Chemicals.

But whether it's an 18650 battery or a 21700 battery, it's a ternary lithium-ion battery.

In 2017, the court used the actual storage capacity of the battery to estimate the salvage value of the 12 Tesla-operated fleets of vehicles auctioned off by EasyRide.

The 12 Tesla Model S have an average range of 160,000 km, an original range of 550 km, an average battery cycle of more than 290, and an estimated average range of just 361 km.

The installation percentage is 34.36 per cent after 160,000 kilometres of decay for these vehicles, which corresponds to a battery that is close to the end-of-life standard, a far cry from the 5 per cent Tesla has officially announced.

This affected consumer confidence in Tesla batteries to some extent at the time, and also severely affected later Tesla models' value retention in the used market.

Even the best Tesla in the industry has been plagued by battery decay, and after 3,000 tests with a three-dimensional lithium battery, Tesla was only able to maintain 70% of its power, so developing a long life is an urgent matter.

Battery management system for 1.6 million km of long-life batteries

Let's not lose sight of another core after the 1.6 million km battery described in the new Tesla patent for the future. The battery is at the heart of the electric vehicle, and the heart of the battery is in the battery management system (BMS).

Many new energy vehicle companies outside China, including Tesla, look at battery management systems as the technology at the heart of their business.

The battery management system is one of the most important systems for electric vehicles, which is related to the safety of the battery and is an important link between the on-board power battery and the electric vehicle.

Its main functions include: battery status prediction, real-time monitoring of battery physical parameters, online security alarms and warnings, charge/discharge control, thermal management, etc.

Of Tesla's "Big Three" electric vehicles, the battery, motor and other components are all externally sourced, with only the battery management system Tesla has been developing in-house.

Most of the core intellectual property applied for by Tesla is related to the battery management system, and the importance of the battery management system for new energy vehicles can be seen.