| 429 / | HD | CHEMISTRY: ELECTRICAL CURRENT PRODUCING APPARATUS, PRODUCT, AND PROCESS |
| 12 | DF | FUEL CELL, SUBCOMBINATION THEREOF OR METHODS OF OPERATING {10} |
| 22 | ![]() | .~ Automatic control means {3} |
| 23 | DF | .~.~> Electrical output dependent |
| 24 | DF | .~.~> Temperature dependent |
| 25 | DF | .~.~> Pressure dependent |