Power-Sonic Sealed Lead Acid Batteries - Technical Manual - Manual (Page 27)

Glossary
Gas Recombination
The process by which oxygen gas generated from the positive
plate during the final stage of charge is absorbed into the
negative plate, preventing loss of water.
High Rate Discharge
A very rapid discharge of the battery. Normally in multiples of C
(the rating of the battery expressed in amperes).
Impedance
The resistive value of a battery to an AC current expressed in
ohms (Ω). Generally measured at 1000 Hz at full charge.
Internal Resistance
The resistance inside a battery which creates a voltage drop in
proportion to the current draw.
Negative Terminal
The terminal of a battery from which electrons flow in the
external circuit when a battery discharges. See Positive Terminal
Nominal Voltage / Nominal Capacity
The nominal value of rated voltage / the nominal value of rated
capacity. The nominal voltage of a lead-acid battery is 2 volts per
cell.
Open Circuit Voltage
The voltage of a battery or cell when measured in a no load
condition.
Overcharge
The continuous charging of a cell after it achieves 100% of
capacity. Battery life is reduced by prolonged overcharging.
Parallel Connection
Connecting a group of batteries or cells by linking all terminals
of the same polarity. This increases the capacity of the battery
group.
Polarity
The charges residing at the terminals of the battery.
Positive Terminal
The terminal of a battery toward which electrons flow through the
external circuit when the cell discharges. See Negative Terminal.
Rated Capacity
The capacity of the cell expressed in amperes. Commonly, a
constant current for a designated number of hours to a specified
depth of discharge at room temperature.
Recombination
The state in which the gasses normally formed within the battery
cell during its operation are recombined to form water.
Series Connection
The connection of a group of cells or batteries by linking
terminals of opposite polarity. This increases the voltage of the
battery group.
Self Discharge
The loss of capacity of a battery while in stored or unused
condition without external drain.
Separator
Material isolating positive from negative plates. In sealed lead
acid batteries it normally is absorbent glass fiber to hold the
electrolyte in suspension.
SLA Battery
Sealed lead-acid battery, generally having the following
characteristics: Maintenance-free, leak-proof, position-
insensitive. Batteries of this type have a safety vent to release
gas in case of excessive internal pressure build-up. Hence also
the term: Valve regulated battery.
“Gel Cells” are SLA batteries whose dilute sulfuric acid electrolyte
is immobilized by way of additives which turn the electrolyte into
a gel.
Service Life
The expected life of a battery expressed in the number of total
cycles or years of standby service to a designated remaining
percentage of original capacity.
Shelf Life
The maximum period of time a battery can be stored without
supplementary charging.
Standby Service
An application in which the battery is maintained in a fully
charged condition by trickle or float charging.
State of Charge
The available capacity of a battery at a given time expressed as a
percentage of rated capacity.
Sulfation
The formation or deposit of lead sulfate on the surface and in
the pores of the active material of the batteries’ lead plates. If
the sulfation becomes excessive and forms large crystals on the
plates the battery will not operate efficiently and may not work at
all.
Thermal Runaway
A condition in which a cell or battery on constant potential
charge can destroy itself through internal heat generation.
Valve Regulated Lead Acid Battery (VRLA)
See “SLA Battery” listed above.
POWER-SONIC Rechargeable Batteries