Fuel Cell Stack
Combines hydrogen with oxygen from the air to generate electricity directly, with water as the only exhaust product. It powers the drive motor and charges a small buffer battery, which exists to smooth demand and recover braking energy rather than to propel the vehicle any distance.
Two hazards here are of a different order to anything else in the corpus. The stack produces several hundred volts of direct current whenever hydrogen and air are supplied — it cannot simply be switched off the way a battery is disconnected. And the vehicle stores hydrogen at several hundred times atmospheric pressure, in tanks whose fittings are not serviceable by a general workshop. Hydrogen leaks are invisible, odourless, and burn with a flame that is nearly invisible in daylight.
Nothing here should be attempted without specific fuel cell training and equipment.
When the stack controller reports something the drive system cannot accept, the designed response is to shut the stack down and run on the buffer battery alone — giving a vehicle that drives normally with drastically reduced range, which is easy to underestimate when refuelling is not available on most routes.
Also known as: fuel cell, hydrogen fuel cell, fuel cell system, hydrogen stack, fcev stack
Referenced by 2 codes
Codes involving this component (2)
Other components in Hybrid Propulsion
- High Voltage Battery 795
- Power Inverter 370
- Motor Generator 249
- Hybrid/EV Battery Pack Sensor Module 243
- Battery Energy Control Module 228
- On-Board Charger 209
- Hybrid Battery Contactor 136
- Charge Port 131
- DC-DC Converter 99
- Inverter Coolant Pump 92
- Motor Current Sensor 73
- Electric A/C Compressor 63
- Inverter Coolant Temperature Sensor 60
- Motor Position Sensor 59
- Hybrid Battery Cooling Fan 54
- Battery Pack Coolant Control Valve 47
- Hybrid/EV Battery Pack Current Sensor 30
- Hybrid Powertrain Control Module 19
- Motor Temperature Sensor 18
- High Voltage Interlock Loop 15
- Drive Motor Control Module 15
- Active Engine Mount 6
- Starter/Generator 6
- High Voltage Service Disconnect 5
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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