Safety Vent
A venting mechanism designed into a cell which activates under specific conditions of abuse to relieve internal pressure.

Secondary Battery
A battery that can be recharged and reused many times.

Secure Waste Landfill
A landfill designed for disposal of normal household trash but which meets government standards designed to protect the environment.

Self-Discharge
The loss of useful capacity of a battery on storage due to internal chemical action (local action).

Separator
An ionic permeable electronically non-conductive spacer or material which prevents electronic contact between electrodes of opposite polarity in the same cell.

Series
The interconnection of cells in such a manner that the positive terminal of the first is connected to the negative terminal of the second, and so on, resulting in increased voltage.

Service Life
The period of useful life of a battery before a predetermined end-point voltage is reached.

Shelf Life
The duration of storage under specified conditions at the end of which the battery still retains the ability to give a specified performance.

Short Circuit
An unwanted electrical connection between a negative and positive source. Short circuits can damage the battery and equipment and can cause sparks or fire.

Short-circuit Current
The initial value of the current obtained from a battery in a circuit of negligible resistance.

Silver/Oxide
A primary battery (non-rechargeable) it is a major contribution to miniature power sources, and is well suited for hearing aids, instruments, photoelectric exposure devices and electronic watches. These cells are primarily made in the smaller “button” sizes.

Slow Charge
Typically an over-night charge lasting abut 14 hours at a charge current of 0.1C. Battery does not require instant removal when fully charged.

Smart Battery
Battery with internal circuit enabling some communication between the battery and the user. Some batteries feature a capacity indicator only, others offer an external bus to interface with the equipment the battery power and the intelligent charger.

Soft Cell
A cell whose voltage rises above its defined boundaries during charging. This voltage rise may be caused by high cell impedance as a result of prolonged battery storage, very cold battery temperature or lack of electrolyte.

Specific Energy
The ratio of the energy output of a cell or battery to its weight (Wh/kg). This term is used interchangeably with gravimetric energy density.

Specific Gravity
The weight of the sulfuric acid electrolyte compared to water.

Spiral Wound
An electrode structure of high surface area created by winding the electrodes and separator into a spiral-wound jelly-roll configuration.

Standby
The use of batteries in which they are charged by an application to be ready for use if the primary power to the application fails. Also called float or backup.

State of Charge
The capacity remaining in a battery.

Sulfation
Growth of lead sulfate crystals in Lead-Acid batteries which inhibits current flow. Sulfation is caused by storage at low state of charge.