French battery maker Saft announced on October 19, 2026, that it is opening a new solid-state battery production line at its Bordeaux site. The line targets aerospace and space applications. It supports sulfide-based and polymer-based electrolytes used at room temperature, and it is meant to move research results into manufacturing and evaluation. In its collaboration with aerospace group Safran, Saft has already delivered semi-solid cells, and the work has entered an evaluation phase aimed at future electric and hybrid-electric aircraft. However, the plan to extend the collaboration to all-solid-state cells and batteries starts in 2027. Opening the facility and putting batteries into aircraft service are still different stages.
Two room-temperature technologies for aerospace and space
Saft, a wholly owned subsidiary of TotalEnergies, says the new line will make it the first manufacturer in France with the capability to develop and produce solid-state batteries using sulfide-based and polymer-based electrolytes at room temperature. The "first in France" positioning is the company's own claim about this combination of technology and manufacturing capability.
Solid-state batteries replace the liquid electrolyte used in conventional batteries with a solid material. Saft cites improved safety and a greater amount of energy stored for a given mass or volume as advantages. The company points to aerospace and space as applications where such improvements are especially valuable, and this announcement is aimed at electrifying both sectors.
The explanation that the line handles two types of electrolyte does not, however, reveal how sulfide and polymer materials might be arranged within a single cell. What was announced is a capability to develop and manufacture multiple technologies. The specific internal design of the batteries and their material formulations were not disclosed.
Delivered cells are semi-solid; the all-solid-state expansion comes in 2027
Safran's announcement of October 15 says the collaboration with Saft has moved from concept studies to evaluation using actual cells. Under the collaboration the two companies unveiled at the 2025 Paris Air Show, the first semi-solid cells have been delivered. A cell is the basic unit of a battery, and those delivered are intended to help validate future aircraft battery systems.
What Saft and Safran announced as delivered in October 2026 are semi-solid cells. The expansion of the collaboration to all-solid-state cells and batteries is planned from 2027.
| When | Announced development | Position in development |
|---|---|---|
| 2025 Paris Air Show | Saft and Safran announce their collaboration | Joint development of next-generation aviation batteries |
| October 15, 2026 | Safran announces delivery of the first semi-solid cells | Shift from concept studies to concrete evaluation |
| October 19, 2026 | Saft announces the opening of the new solid-state line in Bordeaux | Building capability to develop and manufacture multiple technologies |
| From 2027 | Collaboration planned to extend to all-solid-state cells and batteries | Plan to broaden future development targets |
This timeline separates Saft's announcement of the opening from Safran's announcement of the delivery, by subject and development stage. The year 2027 is when the scope of the collaboration is to broaden. It is not a commitment to start mass production of all-solid-state batteries, obtain certification, or install them in aircraft.
According to Safran, the semi-solid cells delivered were developed and manufactured on the new multi-technology line in Bordeaux. In other words, as of the October 15 announcement, production on the new line was already described. The October 19 announcement of the opening should not be read as meaning that cells were first made on that day.
Up to 50% higher density and up to 40% lower CO₂ refer to different things
Saft says the energy density of solid-state batteries can be up to 50% higher than that of conventional lithium-ion batteries. In aerospace applications, where mass and volume are constraints, an improvement in this metric matters. However, the announcement gives no absolute energy-density figure or detailed comparison conditions, and it does not specify whether the value is per unit mass or per unit volume.
For that reason, the "up to 50%" figure cannot be equated with a measured result achieved by the semi-solid cells already delivered, nor does it mean that an aircraft's range would increase by 50%. Energy density and how much energy an entire aircraft uses are separate measures.
The other figure is a reduction of up to 40% in CO₂ emissions from the dry electrode manufacturing process. What Saft targets for reduction are the emissions associated with that specific step of making electrodes. It cannot be extended to a reduction rate for battery manufacturing as a whole, or for the entire lifecycle including aircraft operation.
The 50% relates to the density of energy a battery can store, while the 40% relates to emissions from a particular manufacturing process; the things being evaluated are different. Both are maximum values presented in this company announcement, and judging the performance of individual cells or the effect of the manufacturing equipment would require verified results that include comparison conditions.
Next milestones: cell evaluation and integration into battery systems
The delivered cells are expected to be tested mainly at Safran's system test facility in Niort. That facility handles most of the validation and integration needed for battery systems for future electric and hybrid-electric propulsion. As next steps, Safran cites evaluation of the delivered cells, followed by more advanced battery prototypes and the maturation of the technology for aviation use.
What this sequence shows is the difference between the ability to make and deliver cells and the ability to finish them as battery systems for use in aircraft. The new line and the delivered cells make it possible to proceed with verification using physical hardware. The next task is how to incorporate the results into future propulsion systems.
Information for gauging supply scale remains limited. Energynews also noted that the announcement does not give the new line's production capacity or the amount invested. The opening of the facility shows that a development and manufacturing base is in place, but the announcement offers no figures from which to judge the scale or profitability of commercial supply.
Going forward, the key points to watch are how far cell evaluation and integration into battery systems progress in Niort, and whether that leads to the expansion of the collaboration to all-solid-state cells and batteries from 2027. The applications Saft and Safran envision, electric and hybrid-electric aircraft, lie beyond the process of putting the manufactured cells through testing and developing them to the point where they can be used as systems.