Patent ID: 7344787
Filing Date: 2008-03-18
Classification: F04B,H01M,Y02E

Abstract:
1. A multi-stage compressor system that compresses air supplied to a cathode of a fuel cell system, comprising: a first stage compressor that compresses inlet air to provide a first pressurized air stream at a first pressure; a second stage compressor comprising: a first heat exchanger that enables heat transfer between said second pressurized air stream and said exhaust stream to heat said exhaust stream: and a bypass valve having an open state, a closed state and a partially open state, wherein when in said closed state said first pressurized stream flows to said second stage compressor, when in said open state said first pressurized stream bypasses said second stage compressor and when in said partially open state a portion of said first pressurized stream bypasses said second stage compressor.