The invention relates to a battery. The battery comprises a cathode mix, a lead and a plug, wherein the cathode mix comprises an electrode region and a non-electrode region located at the end part ofthe electrode region, and the size of the non-electrode region is smaller than that of the electrode region; the lead is connected with the non-electrode region; the plug does not react with an electrolyte and is arranged at the end part of the cathode mix, the plug is provided with a through hole for accommodating the lead and the non-electrode region, and the end surface size of the plug is consistent with that of the electrode region of the cathode mix. Through enabling the plug to support the lead and the non-electrode region and enabling the end surface size of the plug to be consistent with that of the electrode region of the cathode mix, after the whole cathode mix is combined with the plug, the outer shape is flat, a depression at the connection place between the non-electrode region and the lead in the case of packaging can be prevented, an electrode sheet can be prevented from damaging the outer package of the battery, and the safety of the battery and the wettability of theelectrolyte are improved.