The intention was to develop new thin-film solar cell technology, but the manufacturing method proved more suitable for use in batteries. Thus, a 'failed' project became a promising start-up in a relatively short period of time.


From phone to car: 50% higher battery performance

LeydenJar has developed a prototype that increases the energy density of batteries by fifty percent. Major suppliers of consumer electronics and car manufacturers are now knocking on the door. The manufacturing method was invented a few years ago by TNO scientist Dr Wim Soppe. Once it became clear that the method was much more suitable for batteries, the idea was patented and a spin-out plan was developed. An entrepreneurial duo took on the challenge, worked out a plan, sought financiers and within a year the company LeydenJar was a fact.

Unique technology

What makes the technology unique worldwide is the use of pure silicon rather than the traditional graphite for the anode part of the battery. Silicon offers a much higher capacity. The difficulty is to process silicon anodes in Li-ion batteries in a mechanically stable way. LeydenJar has succeeded in applying silicon anodes in a porous structure to a copper substrate using a special deposition process. Tests in the lab have shown that the battery's energy density can increase by as much as half.

From smartphone to sustainable storage

These batteries will soon be found in a variety of products: smartphones and other consumer electronics, electrically powered cars and, in time, even storage systems for renewable energy. Decentralized storage systems are an important part of the energy transition and are therefore a potential future market for LeydenJar. In the first instance, the company is focusing on improving battery life in smartphones and electric cars.

Optimising performance

The coming period will be devoted to further improving the performance of the anodes in the battery. The battery size needs to grow, with more and more energy storage per liter and an increase in the number of cycles of charging and discharging to optimize the desired lifetime. Once that is achieved, production of silicon anodes can start and the industry players will have at their disposal a battery that can store 50% more energy for application in their products. The High Tech Campus in Eindhoven will accommodate the anode production plant.

In addition to TNO, LeydenJar works closely with the ZSW knowledge institute in Baden-Württemberg, the Universität Münster and TU Delft. In addition to TNO, UNIIQ, the Brabant Development Company and an informal investor are shareholders on the basis of convertible loans.

In 2019 TNO won second prize in the Impact Delivered category of the EARTO Innovation Awards in Brussels for a prototype that increases the energy density of batteries by 50%. This prototype is being brought to market by LeydenJar. The photo shows Dr Wim Soppe being presented with the award.