Japanese electronic parts company TDK claims to have made a breakthrough in the material of small solid-state batteries, which is expected to significantly improve performance of small electronic devices such as wireless headphones and smart watches.

It is reported that the energy density provided by this new battery (i.e., the energy that can be compressed into a given space) is about 1000 watt-hours per liter (Wh/l), which is about 100 times higher than the battery currently mass-produced by TDK.

The company claimed that its competitors are also advancing the development of small all-solid-state batteries, and that there are currently products with the highest energy density of 50Wh/L. In comparison, rechargeable coin batteries using traditional liquid electrolytes can provide an energy density of about 400 Wh/L.

TDK CEO Noboru Saito said, "We believe that our newly developed solid-state battery material can make a significant contribution to society's energy transformation. We will continue to develop towards early commercialization."

The latest breakthrough

TDK is a well-known Japanese electronic component company around the world. In 2005, it acquired ATL shares in full and expanded its product to the smartphone market. Currently, TDK ATL accounts for more than one third of the global market share of mobile phone batteries and is also a major supplier to Apple.

The new battery developed by TDK will be made of all-ceramic materials and contains solid-state electrolytes of oxide-based and lithium alloy negatives. This battery has high energy storage capacity and will achieve smaller size and longer working time. The oxide material provides high stability and safety. This technology will replace coin-type batteries in existing small electronic products.

TDK plans to provide prototype samples of the new battery to customers starting from next year and hopes to put them into mass production thereafter.

Industry experts believe that this breakthrough is the latest step forward in energy storage technology, but it faces major obstacles on the road to mass production, especially in manufacturing larger batteries.

TDK also pointed out that the ceramic materials used in this battery technology have potential advantages such as safety and portability, but at the same time, production of larger batteries will be more fragile. This is an obstacle in manufacturing batteries for automobiles, and even for smartphone batteries.

Many challenges

Kevin Shang, senior research analyst at data and analytics company Wood Mackenzie, said that the characteristics unfavorable to machining, as well as the difficulties and costs of mass production, are all challenges for solid-state oxide batteries applied to smartphones.

Other industry experts pointed out that the most important application of solid-state batteries may be in electric cars, as it can improve driving range. Currently, Japanese companies are the pioneers in promoting the commercialization of solid-state battery technology: Toyota plans to achieve this goal as early as 2027, Nissan plans to achieve this in 2027, and Honda plans to achieve this by the end of 2030.

However, people still doubt the feasibility of this technology applied to electric vehicles, and how quickly it can be achieved. Zeng Yuqun, founder and CEO of the world's largest electric vehicle battery manufacturer, CATL, said in a media interview in March that solid-state batteries for electric vehicles promoted by Japanese automakers are still several years away from commercialization, and the technology is not perfect enough, lacking durability, and there are still safety issues (such as the consequences of battery rupture in a car accident).