Correct Option: B

Lead–acid batteries, invented in 1859 by French physicist Gaston Planté, are the oldest type of rechargeable battery. Despite having a very low energy-to-weight ratio and a low energy-to-volume ratio, their ability to supply high surge currents means that the cells maintain a relatively large power-toweight ratio. These features, along with their low cost, make them attractive for use in motor vehicles to provide the high current required by automobile starter motors. The lead–acid cell can be demonstrated using sheet lead plates for the two electrodes. However such a construction produces only around one ampere for roughly postcard sized plates, and for only a few minutes. The positive plates are the chocolate brown colour of lead dioxide, and the negative are the slate gray of “spongy” lead.