Gm Global Technolgoy Operations, Inc.

Peter Kilian

Volker Formanski

Sebastian Lienkamp

Marc Becker

Jochen Schaffnit

Remy Fontaine

Oliver Maier

Stephen W Raiser

Thomas Herbig

Peter Willimowski

John P Salvador

Manish Sinha

Steven D Burch

Alastair Gordon Anderson

Josef Kallo

Sebastain Lienkamp

Kilian Simbeck

Systems and methods are provided for regulating the state of charge of a battery. An exemplary electrical system includes a fuel cell coupled to a bus and a battery coupled to the bus via a switching arrangement coupled to a capacitor. An exemplary method for operating the electrical system involves operating the switching arrangement such that a voltage of the battery is substantially equal to a voltage of the fuel cell when a state of charge of the battery is greater than a lower threshold value and less than an upper threshold value, and operating the switching arrangement to couple the capacitor electrically in series between the battery and the bus when the state of charge of the battery is not between the lower threshold value and the upper threshold value.

Switched battery and capacitor arrangement and related operating methods

A method of controlling the ventilation system for an energy source in a fuel cell vehicle is disclosed, which includes an HVAC system, a fluid reserve, and a rechargeable energy storage system (RESS), capable of controlling a temperature of the RESS to militate against damage to or a shortened life of the battery, while maximizing vehicle durability, efficiency, performance, and passenger comfort.

Control method for RESS fan operation in a vehicle

A fuel cell assembly having a flow distribution subassembly that comprises four sets of flow channels, the first set facing an anode for distribution of a fuel reactant to said anode, the second set facing a cathode for distribution of an oxidant to said cathode, the third set in flow communication with said second set and in heat transfer relation with at least one of said anode and said cathode, and the fourth set receiving a coolant different from said oxidant.

Fuel cell design with an integrated heat exchanger and gas humidification unit

A method for gathering information from battery sensors&#x2014;for instance, information regarding the state-of-charge (SOC), temperature and/or other characteristics of battery cells in a vehicle battery pack&#x2014;and using that information to estimate or predict battery degradation or state-of-health (SOH). According to an exemplary embodiment, the method uses both a time-based algorithm and an event-based algorithm to predict or estimate battery degradation. The event-based algorithm may select certain data from the battery conditions (e.g., a state-of-charge (SOC) swing (&#x394;SOC) or an SOC maximum (SOC)), instead of using the entire set of battery condition data, and may use this information in its prediction or estimate.

Method for estimating battery degradation in a vehicle battery pack

A method and system for controlling temperature in an electric vehicle battery pack such that battery pack longevity is preserved, while vehicle driving range is maximized. A controller prescribes a maximum allowable temperature in the battery pack as a function of state of charge, reflecting evidence that lithium-ion battery pack temperatures can be allowed to increase as state of charge decreases, without having a detrimental effect on battery pack life. During vehicle driving, battery pack temperature is allowed to increase with decreasing state of charge, and a cooling system is only used as necessary to maintain temperature beneath the increasing maximum level. The decreased usage of the cooling system reduces energy consumption and increases vehicle driving range. During charging operations, the cooling system must remove enough heat from the battery pack to maintain temperatures below a decreasing maximum, but this has no impact on driving range.

Method for optimized design and operation of battery cooling system in electric vehicles

A system for controlling the power output of a fuel cell stack and a battery in a hybrid fuel cell system. The system includes a power damping filter that receives a power request signal, and damps the request to reduce large changes in the power request. A battery state of charge controller receives the difference between a battery state of charge set-point and the actual battery state of charge, and provides a battery power signal that attempts to maintain the battery state of charge at the set-point. The damped power signal and the battery power signal are added to generate a system power demand signal that satisfies the driver power request using the battery power and fuel cell stack power, and uses the fuel cell stack power to charge the battery during low power transients or if the battery state of charge is below the set-point.

System for controlling the power output of a fuel cell stack and battery

A system and method for reducing RH cycling of the membranes in a fuel cell stack. A control algorithm damps a power request signal using a first order filter during low power transients so that the fuel cell stack continues generating power at a higher rate than is requested. The excess power generated by the stack is used to recharge a battery in the fuel cell system. The damped power signal is weighted so that more fuel cell stack power is provided for a low battery state of charge unless stack power is provided for a high battery state of charge.

Control strategy to prevent humidity cycling in a fuel cell

A propulsion system for a fuel cell hybrid vehicle that includes a fuel cell system and an EESS, where the propulsion system employs an algorithm for increasing system efficiency. A power limit value is defined as the maximum system efficiency times the charge/discharge efficiency of the EESS. If the vehicle operator requests a power greater than the power limit value, then the fuel cell system will preferably provide the power, and if the power request from the vehicle operator is less than the power limit value, then the EESS will preferably provide the power. The algorithm also considers changing operation conditions and parameters that impact the fuel cell system efficiency and the electric energy storage system efficiency, such as the state of charge of the EESS and regenerative braking.

Efficiency optimized hybrid operation strategy

A fuel cell system employing a floating base load hybrid strategy for reducing fast voltage transients of a FCPM. A power request signal is applied to an average power calculation processor that calculates the average power requested over a predetermined previous period of time. A weighting function processor provides a weighting function based on the state of charge of an EESS. The power available from the FCPM and the EESS is applied to a power comparison processor. The available power is compared to the power request to provide a difference value between what is currently being provided and what is desired. The difference value is compared to power limit values of the EESS. The output value of this comparison is added to a filtered value to generate a signal for the change in the output power of the fuel cell stack based on the power request.

Power system for a hybrid fuel cell vehicle that employs a floating base load strategy

Floating base load hybrid strategy for a hybrid fuel cell vehicle to increase the durability of the fuel cell system

Advanced controls concept for hybrid fuel cell systems

A multi-stage compressor system that compresses air supplied to a cathode of a fuel cell system includes a first stage compressor that compresses inlet air to provide a first pressurized air stream at a first pressure. A second stage compressor includes a compression unit that compresses the first pressurized air stream to a second pressurized air stream at a second pressure. A drive unit drives the compression unit using expansion energy of an exhaust stream of the fuel cell. A first heat exchanger enables heat transfer between the second pressurized air stream and the exhaust stream to heat the exhaust stream.

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Heidelberg, Germany

Peter Kilian