蓄电池（Storage battery），俗称电瓶，又称可充电电池（Rechargeable battery），泛指所有在电量用到一定程度之后可以被再次充电、反复使用的化学能电池的总称。之所以可以充电是因为甚化学作用在接上外部电源后其化学作用能反向进行。制成蓄电池的化学品有很多种，其设计上亦各有不同；因此，其电压、容量、外观大小、重量也各有不同。现在日常生活中普通使用的有：

现时，蓄电池被广泛地应用于各设备上，包括汽车起动器、各种手提设备及工具、不断电系统等。混合动力车辆及纯电动车对蓄电池的要求使得蓄电池的技术不断改进，以求减低成本，改善性能，例如减轻其重量及增加其寿命。相对一次电池，蓄电池对环境的影响较低，以整个寿命周期计碳排放较少，而大多数的蓄电池都可以循环再造。虽然蓄电池的的起始成本较高，但由于可以多次重复使用，平均计其成本反而比一次电池便宜。尝试给非蓄电池（原电池）充电是不可取的，因为这可能引起电源漏出有害液体、发热、起火甚至爆炸。

A rechargeable battery, storage battery, secondary cell, or accumulator is a type of electrical battery which can be charged, discharged into a load, and recharged many times, while a non-rechargeable or primary battery is supplied fully charged, and discarded once discharged. It is composed of one or more electrochemical cells. The term "accumulator" is used as it accumulates and stores energy through a reversible electrochemical reaction. Rechargeable batteries are produced in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network. Several different combinations of electrode materials and electrolytes are used, including lead–acid, nickel cadmium (NiCd), nickel metal hydride (NiMH), lithium ion (Li-ion), and lithium ion polymer (Li-ion polymer).