A pilot line built in March 2023
Samsung SDI is a South Korean company that makes batteries for electric cars and other devices. In March 2023, it set up a pilot production line, a small scale line built to test how a battery can be made before building it at full size, at its Suwon research center. The line was for an all solid battery, a lithium battery that swaps the liquid material carrying charge between its 2 terminals for a solid one. Samsung SDI formed a dedicated commercialization team that December, the group responsible for turning pilot line output into a sellable product.
Why the company says it cannot wait
That same December, Go Joo young, executive vice president and head of strategic marketing at Samsung SDI, explained why the company was pushing the technology.
To overcome the shortcomings of existing lithium-ion batteries, all-solid-state battery technology is the answer. We will not lose our first-mover advantage in this field.
Go Joo young, executive vice president and head of strategic marketing at Samsung SDI. Source 4.
The chemistry behind the line
The design uses a sulfide solid electrolyte, a sulfur based solid material that carries charge instead of the flammable liquid inside a conventional cell. It avoids a lithium metal anode, the negative electrode inside a cell, to prevent dendrites, needle shaped growths that can cause a short circuit. In December 2023, Samsung SDI said it was targeting an energy density, how much energy a cell stores for its size, of over 900 watt hours per liter.
A sample customers saw
By October 2024, Samsung SDI had a cell to show. At a mobility expo in Daegu, the company displayed an all solid battery cell rated at 900 watt hours per liter, built with a cathode free structure, a design that removes the separate cathode material layer inside a cell. Samsung SDI said it had already distributed samples of the battery to unnamed clients in 2023 and received positive responses. No source names which clients saw those samples.
Company wide research and development spending across every battery type Samsung SDI makes, not spending on the all solid battery program alone. None of the 5 sources breaks that figure out separately.
Show the numbers
| 2023 | 1.1 |
| 2024 | 1.3 |
| 2025 | 1.4 |
One automaker signs on
In 2025, Samsung SDI signed a joint memorandum of understanding with BMW, a document in which 2 companies agree to work together, not yet a sales contract, to develop the all solid battery. In a separate agreement the same year, Samsung SDI signed a joint memorandum of understanding with Hyundai Motor for something the company calls a robot battery. Samsung SDI does not state that the robot battery uses the same solid battery chemistry, so the 2 agreements describe 2 different programs. No source says BMW has received or tested a sample of the all solid battery.
Company wide capital spending across every battery type Samsung SDI makes, not spending on the all solid battery program alone. None of the 5 sources breaks that figure out separately.
Show the numbers
| 2023 | 4.3 |
| 2024 | 6.6 |
| 2025 | 3.3 |
What the newest filings do not say
Samsung SDI own newest quarterly earnings materials, filed in July 2026, cover its financial results and its outlook for storage batteries, electric car batteries, small batteries and electronic materials, and name sodium ion battery development as a 2026 priority. They do not use the words all solid, ASB or solid state anywhere. That silence does not prove the pilot line stopped, and it does not prove it kept running either. No source among the 5 read for this article says an electric car has been built, driven or tested on this chemistry.