The present application provides a battery state estimation method, which relates to the field of battery technology. The battery state estimation method includes: obtaining a first cell state parameter of each of a plurality of cells in a battery; under a condition that there are multiple cell partitions, determining whether the first cell state parameter of each cell belonging to a cell partition is within a first cell state parameter range corresponding to the cell partition; when it is within the first cell state parameter range corresponding to the cell partition, estimating a cell state of each of the cell partitions based on a target cell state parameter corresponding to the cell partition; and estimating a battery state of the battery based on the cell state.