| 摘要 |
<p>A group of lead acid batteries has a state of charge indicator placed such that the user, typically the driver of an electrically propelled vehicle, can maintain a constant watch on the state of the batteries. The charge indicator is based on the use of a suitable density float (7) acting as a hygrometer. The floats are either spherical or cylindrical and they are made of some magnetic material, the position of which activates some form of reed relay (10) in circuit with a warning lamp (13). The hygrometer position can either be a built-in compartment (4) on the side of the battery wall or in a position between the plates of the battery.</p> |
