Sinovoltaics finds widening financial gap among energy storage suppliers

Technical engineering firm Sinovoltaics said its latest financial stability ranking, which tracks Altman Z-scores for 65 energy storage manufacturers, shows that Tesla, Delta Electronics, and Hyundai Electric hold the top three spots.

The Altman Z-score is a standard financial model that combines profitability, leverage, liquidity, solvency, and activity ratios into a single measure of a company’s financial health. The latest ranking, covering September 2023 through June 2026, is the third edition Sinovoltaics has published this year.

The report found 30 companies in the “safe zone,” with Z-scores above 2.6, up from 26 at the start of the tracking period. Another 18 companies fell into the “grey zone,” between 1.1 and 2.6, while 17 scored below 1.1, a threshold Sinovoltaics associates with elevated bankruptcy risk over the following two years. Six of those companies posted negative scores, which Sinovoltaics said signals severe financial distress.

Sinovoltaics said diversified industrial and energy-management suppliers – including Tesla, ABB, Delta Electronics, Eaton, Siemens Energy, and GE Vernova – posted an average Z-score of 5.54 last quarter, comfortably inside the safe zone. Inverter and power-conversion-system makers averaged 3.26, also in the safe zone. Battery cell and pack manufacturers averaged 2.03, in the gray zone, while solar module makers averaged 1.13, just above the elevated-risk threshold.

“What we’re seeing is a maturing market rewarding balance-sheet depth over pure growth,” Arthur Claire, Sinovoltaics’ director of technology, said in the report. “Companies that diversified beyond a single product line are compounding that advantage, while suppliers exposed to one segment, whether that’s cells, modules or storage integration, are absorbing the full force of the current margin compression.”

Standalone storage integrators fared worst, averaging 0.08. Eos Energy Enterprises, Stem Inc., and ESS Tech all posted negative scores. Sinovoltaics said ESS Tech’s score fell from -2.29 to -27.95, the sharpest decline in the ranking. Not every company starting from a weak position lost ground: GE Vernova, HyperStrong, and SolaX Power all moved from near-zero scores into safe-zone territory, and Eos Energy Enterprises improved from -10.38 to -3.77 despite remaining in severe distress.

Sinovoltaics’ previous edition of the ranking, published in November 2025, tracked 60 manufacturers and had Tesla, Mustang Battery, and Solid Power in the top three spots, with 23 companies in the safe zone. The new edition expands the tracked pool to 65 manufacturers and shows 30 in the safe zone.