Preventing Quality Problems
Reduction of Battery Voltage and Deterioration of Capacity
(1) Reduction of battery voltage and deterioration of capacity through contact with antistatic
Incidents have been reported where terminal-mounted batteries for memory backup or coin-type lithium batteries have
come into contact with antistatic conductive materials, thus forming external discharge circuits and leading to voltage drops
or capacity deterioration.
In manufacturing plants using ICs, LSI and other semiconductor components, thoroughgoing antistatic measures are taken.
Various protective materials are used to prevent static: most of them have special compounds of carbon, aluminum foil and
other metals and are therefore conductive. These protective materials are used, for example, in the form of packaging bags,
trays, mats, sheets, films, corrugated boards and resin cases.
A protective material may have a resistance ranging from 10
terminals of a battery come into contact with this material, a current ranging from several milliamperes to several microamperes
will flow and the battery will discharge, causing voltage drop and capacity deterioration.
A terminal-mounted battery was inserted into a
conductive mat. The battery charge was exhausted
in several days.
Battery-mounted PC boards were inadvertently
brought into contact with spacers and a conductive
rubber sheet. The battery
charge was exhausted.
A battery-mounted PC board was inadvertently
brought into contact with a conductive resin case.
The battery charge was exhausted.
Conductive resin case
This information is generally descriptive only and is not intended to make or imply any representation, guarantee or warranty with respect to any cells and batteries. Cell and battery designs/specifications
are subject to modification without notice. Contact Panasonic for the latest information.
/cm, for instance. This means that if the (+) and (-)
A battery was placed directly
on a rubber sheet spread over
a worktable. The (+) and (-)
terminals were in contact with
t h e s h e e t a n d t h e b a t t e r y
charge was exhausted.
When batteries are to be used near protective materials,
take every possible care to ensure that the (+) and (-)
terminals of the batteries or PC boards, etc. on which
batteries are mounted do not touch these protective
Exclusive grounding line
Conductive rubber sheet