PEM battery flow field plate structure with multiple flow channel widths

The invention discloses a PEM battery flow field plate structure with multiple flow channel widths. The structure comprises a plate body, and a reaction gas inlet and a reaction gas outlet are formedin the plate body, wherein a plurality of flow channel fields which are sequentially communicated are arranged between the reaction gas inlet and the reaction gas outlet. The first flow channel fieldis communicated with the reaction gas inlet, and the last flow channel field is communicated with the reaction gas outlet; each flow channel field is provided with a plurality of runner shoulders, anda single flow channel is formed by every two adjacent flow channel shoulders, wherein the widths of the flow channels of all stages of flow channel fields are sequentially decreased. The invention has the effective effects that the flow field structure conforms to the generalized Murphy law, and the flow field structure with the multi-stage flow channel width change is designed and is similar toa multi-stage hole structure