Multiple injection fuel cell and operating method thereof

Patent metadata

Field	Value
Publication number	US-2016308227-A1
Application number	US-201615193431-A
Country	US
Kind code	A1
Filing date	Jun 27, 2016
Priority date	May 9, 2011
Publication date	Oct 20, 2016
Grant date	—

Abstract

Fuel cell batteries are provided, and in particular hydrogen fuel cell batteries composed of at least one stack of cells. The battery is divided into at least two groups of cells able to be supplied with hydrogen separately. In a first phase, only the first group of cells and not the second is supplied; unconsumed hydrogen may however flow between the two groups via at least one evacuation manifold connected to the cells of the two groups. In a second phase, the supply to the two groups is reversed, unconsumed hydrogen still being able to flow between the two groups via the evacuation manifold. In a third phase, after a series of alternations of the two first phases, the two groups are first simultaneously supplied, then a purge valve of the evacuation manifold is opened then closed.

First claim

1 . A fuel cell battery producing electrical power via an electrochemical reaction between at least two reactants, the battery comprising at least one stack of cells each of which is composed of an assembly of an electrolyte, an anode, and a cathode, the stack being provided with a means for supplying at least one of the reactants, this means being able to deliver this reactant to the cells of the stack, and a means for evacuating sub-products of the reaction, wherein:
the cells of the battery are divided into N groups, N>1, and the means for supplying the reactant comprises a respective supply manifold for supplying each group of cells, this manifold being able to deliver the reactant selectively to the cells of a group without delivering it to the cells of the other groups, the supplying means furthermore comprises a selective switching means for permitting and preventing the passage of the reactant to each of the manifolds, the evacuating means comprises at least one evacuation manifold, it is arranged in order to permit reactant not consumed by the reaction to flow, between the N groups of cells, and it comprises a purge valve, and the cells of the various groups are stacked in an interleaved way in one and the same stack, which is to say that a cell of one group is adjacent a cell of another group in the stack.

2 . The fuel cell battery as claimed in claim 1 , wherein the evacuation manifold, passing through the stack of cells, communicates with the cells of all the groups.

3 . The fuel cell battery as claimed in claim 1 , wherein the supplying means supplies hydrogen to the supply manifolds of the N groups, the manifold of a group communicating with the cells of this group from the anode side.

4 . The fuel cell battery as claimed in claim 1 , wherein the supplying means supplies oxygen to the supply manifolds of the N groups, the manifold of a group communicating with the cells of this group from the cathode side.

5 . The fuel cell battery of claim 2 comprising an outlet and a drain system, said drain system comprising at least a drain channel and, in which said outlet is arranged downstream the said purge valve of said evacuation manifold and a said drain channel is arranged to permit a flow between one said supply manifold and the said outlet.

6 . The fuel cell battery of claim 5 in which at geometrical feature of a said drain channel is configured to limit the fluid flow of a reactant in the said drain channel to at most 5% a fluid flow of a reactant in a said supplying mean.

7 . The fuel cell battery of claim 5 in which a said drain channel comprises a valve adapted to permit, prevent or limit the fluid flow of a reactant in the said drain channel.

8 . The fuel cell battery of claim 7 in which a fluid flow of a said drain channel is controlled by a said valve, the opening of the said valve being controlled according to a representative value of the fluid flow of a reactant in the said drain channel.

9 . The fuel cell battery of claim 7 in which said evacuation manifold comprises at least a phase separator adapted to collect liquid water in the said evacuation manifold, said phase separator being arranged in the fluid path connecting two neighboring groups.

10 . A method for supplying a fuel cell battery, comprising at least one stack of cells, with at least one reactant, wherein N groups of cells of the battery, N>1, are selectively supplied with the reactant in at least three phases,
a) a first phase in which a first group of cells is supplied but not a second group, the unconsumed reactant being able however to flow between the two groups via at least one evacuation manifold connected to the cells of the two groups; b) a second phase in which the second group is supplied but not the first, the unconsumed reactant being able however to flow between the two groups via the evacuation manifold; and c) a third phase in which the two groups are first supplied simultaneously, then a purge valve of the evacuation manifold is opened then closed.

11 . The method as claimed in claim 10 , wherein the cells of the various groups are stacked in an interleaved way in one and the same stack, which is to say that a cell of one group is adjacent a cell of another group in the stack.

12 . The method as claimed in claim 10 , wherein the two first phases are repeated in a plurality of successive alternations before the third phase is passed to, after which a cycle restarts.

13 . The method as claimed in claim 10 , wherein N is greater than two and either a single group is supplied during a phase or a plurality, but not all, of the groups are supplied by modifying the composition of the groups supplied during a series of successive phases via a gradual permutation of the supplies, then a purge phase is carried out comprising simultaneously opening all the supplies, immediately followed by a common purge via the purge valve.

14 . The method as claimed in claim 13 , wherein the series of phases is repeated a plurality of times before the purge phase.

15 . The method as claimed in claim 10 , wherein the battery is a fuel cell battery and the reactant is hydrogen delivered by the supply manifolds to the anode side of the cells of each group.

16 . The method of claim 10 wherein an evacuation manifold, passing through the stack of cells, communicates with the cells of all the groups, wherein the said fuel cell comprises an outlet arranged to permit the evacuation of fluids out of the said fuel cell, and a drain system comprising at least a drain channel, said drain channel being arranged between a supply manifold of a group of cells, so-called last group, communicating with the group of cells which is supplied by reactant, so-called first group, and wherein a fluid is evacuated through a said drain channel in at least a phase chosen between a first phase a) and second phase b).

17 . The method of claim 16 in which the said drain is adapted to limit reactant flow rate in a said drain channel to at most 5% of a reactant flow rate in a manifold supplying a first group.

18 . The method of claim 16 in which, in at least a phase chosen between a first phase a) and second phase b), the evacuation of fluid from a last group, is blocked then permitted by a said drain system.

19 . The method of claim 16 in which a said drain system allows, in at least a phase chosen between phase a) and phase b), the evacuation of a fluid from a said last group.

20 . The method of claim 16 in which, in at least a phase chosen between phase a) and phase b), circulating liquid water is collected by a phase separator arranged in the fluid path connecting two neighboring groups, preferably connecting a said first group and a neighboring group.

21 . The method of claim 16 which the series of phases is repeated a plurality of times before the phase c).

22 . The method of claim 16 in which, the direction of the reactant flow in a said last group is identical in phase chosen between phase a) and phase b) and in phase c).

23 . The fuel cell battery as claimed in claim 2 , wherein the supplying means supplies hydrogen to the supply manifolds of the N groups, the manifold of a group communicating with the cells of this group from the anode side.

24 . The fuel cell battery as claimed in claim 2 , wherein the supplying means supplies oxygen to the supply manifolds of the N groups, the manifold of a group communicating with the cells of this group from the ca

Assignees

• Commissariat Energie Atomique

Inventors

• Poirot-Crouvezier Jean-Philippe

Classifications

• H01M8/04753 Primary

  of fuel cell reactants · CPC title

• H01M8/04089

  of gaseous reactants · CPC title

• H01M8/04179

  by purging or increasing flow or pressure of reactants · CPC title

• H01M8/249

  comprising two or more groupings of fuel cells, e.g. modular assemblies · CPC title

• H01M8/04761

  of fuel cell exhausts · CPC title