Why Develop Solid State Battery?

What is solid state battery?

Solid state battery work on the same principle as lithium-ion battery, consisting of a positive electrode, a negative electrode and an electrolyte. The difference is that the electrolyte of lithium-ion battery is usually liquid, while solid state batteries use solid electrodes and solid electrolytes.

Common lithium-ion batteries on market have separators and electrolytes to separate the positive and negative electrodes. Solid state batteries use solid electrolytes and also act as separators.

The safety of the battery is very important. Lithium-ion batteries use electrolyte, which may cause the battery to expand due to temperature changes, or may be damaged due to external impact and cause leakage. The stability advantage of solid battery is very obvious. The stability of solid state electrolyte also makes the safety very high, even if the electrolyte is damaged, it is safe.

Material

From the perspective of battery structure design, compared with traditional liquid batteries, there are not many changes in the commercial positive and negative electrodes of solid state batteries (positive electrode: high nickel positive electrode; negative electrode: silicon carbon, pre-lithium, Li metal, etc.).

Semi-solid battery still requires separators and electrolytes (the amount of electrolyte is gradually reduced, and depending on the system, some use separators and some do not). Only all solid state batteries do not require a separator (electrolyte, separator, and electrolyte are replaced with solid electrolytes).

Solid electrolyte is the core component of the solid sate system. The type of material largely determines various performance parameters of the battery, such as cycle stability、safety、power density and high and low temperature performance. Solid electrolyte mainly include polymers, oxides, and sulfide electrolytes. 

Why develop solid state batteries?

Solid state batteries (SSB) can add battery capacity to electric vehicles. According to the current situation of the market, electric vehicles have replaced part of the internal combustion engine vehicle market, but people often feel range anxiety. “What should I do if the car is about to run out of power?” To stabilize the status of electric vehicles, it is important to improve the mileage and endurance of electric vehicles.

According to a poll, 35% of Americans surveyed hope that the range of electric vehicles can reach more than 800 kilometers. With the current level of technology, few car companies can achieve this level.

Another type of future batteries: Sodium ion Battery

Advantages of Solid-State Batteries

Generally speaking, increasing the battery capacity can increase the number of batteries. Which not only increases the cost of battery, but also increases the weight and space of the car. In terms of future battery technology, the obvious advantages of solid state batteries for electric vehicles are suitable for increasing electric vehicle battery capacity:

• High energy density, solid-state batteries can store more power
• All solid and have no flammable liquid, so it will not cause explosion or fire. Reduce the space for safety components and put in more batteries
• Lighter weight, and even electric flight can be achieved in the future (NASA is developing solid state batteries for power aircraft)
• Faster charging, solid state batteries charge much faster than liquid electrolyte batteries, charging time is 10 minutes or less, no need to wait for hours
• Longer battery life and eliminating capacity fading caused by side reactions of traditional lithium battery liquid electrolytes

Application

Solid state batteries are already used in medical applications such as pacemakers, wearable devices and RFID. Solid state batteries have not yet entered the market of electric vehicles, but major car companies are very interested in the research and development of solid state batteries.

Which companies are manufacturing solid state batteries?

From battery manufacturers to universities, such as Harvard University in the United States, which is studying this technology, QuantumScape, Samsung and Toyota have also invested heavily in the research and development of solid-state battery.

QuantumScape

QuantumScape was founded by Stanford University scientists Jagdeep Singh, Fritz Prinz and Tim Holme, and has more than 200 patented solid state battery technologies. The company has received investment support from Bill Gates, Volkswagen Group, Continental Group and SAIC Motor. With a current market value of nearly US$20 billion, it has become a leader in the research and development of solid state battery technology.

ACC

Automotive Cells Company (ACC) and ProLogium Technology (hereinafter referred to as “Huineng Technology”) signed a memorandum of agreement to cooperate in the development of solid state batteries for electric vehicles (EV).

Solid Power

Solid Power was founded in 2011 with initial funding from Hyundai Motor Company and other investors. In addition to the BMW Group, the company also has a partnership with Ford. The company is producing solid state batteries.

Toyota Automotive

According to market rumors, Toyota will launch a car equipped with an advanced solid state battery in 2025, which can charge for 10 minutes and have a range of 1,200 kilometers, and the weight, volume and cost of the battery can be halved.

Panasonic

Panasonic Holdings said it will mass-produce small all-solid-state batteries currently being developed for drones and other applications in the second half of the 2020s. The company said that if it can be put into practical use, it is expected to be able to charge 80% of the drone’s battery capacity in about 3 minutes.

Nissan

Nissan recently stated: “Solid-state batteries have been successfully developed and the goal is to start trial production in 2025 and be suitable for mass production vehicles from 2028.”

Honda

Honda plans to launch a demonstration production line for all solid-state batteries in 2024, and the batteries produced will be used in models launched in the second half of the 2020s

Future Outlook

Solid state batteries are still being developed, and there are great challenges in transforming them into mature products. The materials used in the initial development stages of solid state batteries are more expensive and more complex to produce. It is very difficult to launch the market in a short time. Many media outlets believe that solid state batteries will ultimately be the batteries of the future for electric vehicles.