US battery developer Factorial announced on November 10, 2026, that it recorded its first revenue from aerospace battery cells in the third quarter (July–September): $26,000. The company had previously expected to book its first revenue in 2027, so commercial supply has begun ahead of schedule. Factorial also said it has achieved an energy density of 450 Wh/kg, a measure of stored energy per unit of weight, in its aerospace cells.
However, the 450 Wh/kg figure for Solstice, a separate all-solid-state battery, is a design target rather than proven performance. This distinction matters when assessing Factorial's technical and commercial progress. Now that aerospace cell sales have translated into actual revenue, the next challenge is whether the company can build a system to produce high-performance cells reliably and run a profitable business.
First revenue of $26,000 from aerospace cells
According to a shareholder letter signed by co-founder and CEO Siyu Huang, Factorial booked its first revenue from an aerospace customer ahead of the originally planned 2027. The company began delivering battery cells under a commercial order it won in July. Revenue in the same period a year earlier was zero, and the $26,000 also equals the company's cumulative revenue for January–September 2026.
The amount is small, but moving from winning an order to delivering a product and recognizing revenue is significant. According to Factorial's quarterly report (Form 10-Q), the company recognizes revenue when it has satisfied its contractual performance obligations and control of the product has transferred to the customer under the shipping terms. Simply sending evaluation cells to a customer would not necessarily meet those conditions. With revenue now on the financial statements, it is possible to confirm that the paid supply was established as a commercial transaction.
Still, recognizing revenue is not the same as having collected payment. Neither the shareholder letter nor the 10-Q discloses the first customer's name, the number of cells delivered, or the unit price. The $26,000 figure alone therefore cannot be used to infer the size of the order or production volume, and it remains unclear at this stage whether this will become a sustained business.
The 450 Wh/kg aerospace cell and the solid-state battery in development
Factorial's aerospace cells are based on the design of its polymer-based solid-state battery technology, FEST, and use a lithium-metal anode. Solstice, which the company is developing for automotive use, is a sulfide-based all-solid-state battery that uses no liquid electrolyte. The two use different battery technologies, and their development and commercialization progress is not the same.
According to the Q3 2026 shareholder letter (pp. 2, 7, 9) the company published, the 450 Wh/kg energy density is a performance level already achieved in aerospace cells, whereas for Solstice it is set as a design target.
| Cell type | Status of 450 Wh/kg (as of Nov. 10, 2026) | Supply / development status |
|---|---|---|
| Aerospace lithium-metal cell (FEST-based) | Achieved | Paid supply to aerospace customers has begun and first revenue recorded. However, it is unconfirmed whether the cells sold met the 450 Wh/kg specification |
| Solstice (sulfide-based all-solid-state battery) | Design target of up to 450 Wh/kg | Cells of up to 40 Ah have been produced and shipped to partners for development and validation. However, simultaneous achievement of 40 Ah and 450 Wh/kg is unconfirmed |
Thus, while Solstice cells of up to 40 Ah have been made and have reached the partner validation stage, it cannot be confirmed that those cells achieved an energy density of 450 Wh/kg. Both figures come from Factorial's own announcements, and because the battery types and development stages differ, they are not the result of a comparison under identical conditions.
For its aerospace cells, Factorial says the 450 Wh/kg now achieved is about 15% higher than the energy density of the cells used in a drone that set a flight record in 2026. A Titan Dynamics Group I drone (20 pounds or less) powered by Factorial cells flew for more than eight and a half hours in July. However, 450 Wh/kg was reached afterward, and the record flight did not use 450 Wh/kg cells. Nor can it be concluded from the announcement that this performance had been achieved by the end of September.
Moreover, the roughly 15% improvement compares only the gravimetric energy density of the cell itself. It does not mean that the energy density of the whole battery pack, or the drone's flight time, improves by the same proportion. The shareholder letter also does not give detailed test conditions for the 450 Wh/kg cells or specific data on their lifespan under repeated charging and discharging.
Leveraging existing manufacturing equipment to build toward mass production
Factorial says up to 80% of conventional lithium-ion battery production equipment can be reused in the FEST manufacturing process. Reusing existing equipment is intended to hold down capital investment, but the equipment reuse rate alone cannot determine manufacturing cost or profitability. According to the company, yield on its pilot line, used for trial production, exceeded 85%. That is a pilot-line result, however, and does not mean the same yield has been achieved at partners' mass-production facilities.
The company envisions different supply structures by application. For high-performance uses such as aerospace, it plans to sell finished cells made on its own lines, using contract manufacturing externally as needed. For automotive, it anticipates a business model combining contract manufacturing and technology licensing. Starting aerospace sales therefore does not in itself mean a mass-production system for automotive has been established.
Partnerships toward mass production are also advancing. The memorandum of understanding (MOU) Factorial signed with South Korea's SK On in July is for jointly evaluating the feasibility of production using existing manufacturing networks. For Solstice, it signed a joint development agreement with Mitsui Kinzoku in September, under which Mitsui Kinzoku will develop the sulfide solid electrolyte. POSCO Future M is responsible for developing cathode and anode materials. These are efforts to evaluate manufacturing equipment compatibility and advance materials development, not a stage at which mass production has been committed.
Factorial plans to complete the expansion of its FEST production lines by the end of 2027 and its Solstice lines by the end of 2028. These are schedules for building out production facilities, however, and do not indicate when the batteries will be installed in mass-produced vehicles or when vehicles will launch. While the company won an order for a supercar in January, it positions signing a volume purchase agreement with a mainstream automaker as its next major goal. If such a contract is concluded, it expects to scale up production by the end of the 2020s, but that will require a formal agreement with customers.
First revenue booked, but manufacturing cost and profitability remain challenges
One challenge Factorial faces on the road to commercialization is high manufacturing cost in the early production phase. According to the shareholder letter, low production volumes currently mean large fixed costs are allocated to each cell, and material costs are also high. As a result, the manufacturing cost per cell exceeds the expected selling price. The company expects scaling up production to bring costs down but has not said when profitability will improve.
Cost of revenue in the third quarter reached $1.831 million. Most of that, $1.779 million, came from an inventory write-down, an expense incurred from reducing the carrying value of inventory to net realizable value. The 10-Q also says cost of revenue includes labor, manufacturing overhead, and material costs associated with producing drone cells.
For this reason, the entire $1.831 million in cost of revenue is not the cost incurred directly to manufacture the cells sold this time. Dividing cost of revenue by the $26,000 in revenue does not yield an accurate per-cell loss or loss rate. The figure should be understood as including the inventory write-down and the cost burden of low-volume production.
Meanwhile, third-quarter net income under US GAAP was $8.84 million. However, operating loss was $16.435 million, so the battery cell sales business has not turned profitable. The net profit was driven largely by a $24.012 million non-cash gain from the revaluation of warrant liabilities tied to stock warrants. In other words, this bottom-line profit should be considered separately from any improvement in the core business's earning power.
Factorial expects to book more substantial commercial revenue in 2027 and anticipates that, until then, revenue will remain small and fluctuate from quarter to quarter. The first revenue is an important milestone showing the aerospace battery business has moved from research and development to commercial supply, but the business's sustainability has yet to be proven. The focus going forward will be whether Factorial can win repeat orders in aerospace, reduce manufacturing cost as production volume grows, and sign a volume purchase agreement with a mainstream automaker. Progress on these fronts will show whether this first revenue leads to sustained growth.