6. In Case of Fire
6.4 High
Voltage Battery Re-ignition by Stranded Energy
Damaged
cells
in
the
high
voltage
battery
can
experience
thermal
runaway*
and
re
-
ignition.
To
prevent
rei
-
gnition,
the
first
responder
and
second
responder
need
to
be
aware
of
the
risk
of
stranded
energy*
which
remains
in
the
damaged
cells
and
can
lead
to
re
-
ignition.
*Thermal runaway : The originating cause of thermal runaway is generally short-
circuiting inside a battery cell and a resulting increase in the cell’s internal temperature.
Battery produces heat with thermal runaway and it can spread from one battery cell to
many cells, in a domino effect.
*Stranded energy : Energy remains inside any undamaged battery cells after the
accident. Stranded energy can cause a high voltage battery to reignite multiple times
after a fire has been extinguished.
How to Prevent Re-ignition (Mitigating Stranded Energy Risk)
1. 12V battery (-) terminal disconnection (To depower battery management system)
2. High voltage shut off
*refer to page 12
3. Discharging the high voltage battery
*refer to page 27
24
OPTIMA PHEV
