VeriFone VX 685 GPRS, Installation Manual

Page: 50 / 56

B
ATTERY
I
NFORMATION
Charging
50
VX 685/VX 690 I
NSTALLATION
G
UIDE
Low Self-Discharge Rate
Lithium-ion batteries have a lower self-discharge rate compared to other types of
battery (the self-discharge rate for a lithium-ion battery is less than one-half of that
of a nickel-cadmium battery). This means that once they are charged, they will
retain their charge for a longer time than other types of rechargeable batteries.
Other battery types can lose anywhere from 1-5% of their charge per day,
(depending on the storage temperature) even if they are not installed in a terminal.
Lithium-ion batteries will retain most of their charge even after months of storage.
High Voltage Capacity
Lithium-ion batteries operate at higher voltages than other rechargeable batteries,
about 3.6 volts for lithium-ion versus 1.2 volts for nickel-metal-hydride or nickel-
cadmium batteries. This means a single cell can often be used rather than
multiple metal-hydride or nickel-cadmium cells.
Precautions Observe the following precautions when handling lithium-ion batteries.
Aging Effects
Battery packs are subject to aging, even when they are not used.
•
Aging leads to deterioration in capacity or battery life.
•
Batteries fail after 2 or 3 years, or approximately 300 charge-discharge cycles.
•
Chemicals may also affect the aging properties of batteries.
Transportation Restrictions
•
It is illegal to ship fully charge batteries by air because they may cause
accidental explosions.
•
Shipment of large quantities of lithium-ion batteries may be subject to
regulatory control.
Storage Precautions
•
Do not fully charge batteries before storage. Keep the batteries partially
charged before storing them, then charge them fully before actual usage.
TIP
Storing the battery in a cool environment (25
°
C or less) at 40% charge reduces
the effects of aging.
NOTE
These precautions do not apply to personal carry-on battery packs.