Alpha Technologies AlphaCell GelCell Series - Manual (Page 22)

745-680-C0-002, Rev.B 22
5.0 Battery Symptoms and Solutions
Problem with Symptom Possible Causes Possible Result Corrective Actions
Capacity Test
Results
Reduced operat-
ing time at 77°F
(25°C) with
smooth voltage
decline
Normal life cycle
Eventual failure to support the
load followed by potential for
shorted cells
Replace battery system
when at 70% of rated
capacity or before
Reduced operat-
ing time at 77°F
(25°C) with steep
voltage decline or
voltage plateaus
Individual low capacity cells
Reversed cells during discharge
Reversed cells will become very
hot and will not fully recharge
Replace the isolated low
capacity batteries
Excessive initial
voltage drop even
to the point of
dropping load in
the first several
seconds
Battery is extremely cold •
Cabling is too small •
gauge
High resistance •
connections
Battery is undersized •
Shorted cells •
Excessive voltage drop •
Cells will become hot, could •
develop thermal runaway;
internal arcing could result in
an explosion
Heat the battery •
Run parallel cables •
or increase gauge of
cables
Clean and reassemble •
connections
Add required parallel •
strings
Replace isolated •
units with shorts and
evaluate entire string
Visual Battery
Checks
Cover or container
crack
Handling or impact damage
Cell dryout or ground fault.
Potential internal gas ignition
Replace damaged unit.
Cover or container
explosion
Ignition of cell internal gasses
due to external source,
fusing, or internal conductive
path or internal spark due
to shorting. Potential exists
for ill-maintained batteries or
those left in service beyond
useful life.
Personal injury and equip- •
ment damage at time of
explosion.
Failure to support load. •
Replace damaged unit and
evaluate balance of string.
Burned area on
container
Crack in container wicking
electrolyte to grounded rack.
Ground fault
Could result in
personal hazard due to •
conductive path to rack
smoke or battery fire •
thermal runaway •
Clear the ground fault and
replace defective unit. Evalu-
ate balance of string.
Permanently
deformed
(swollen) container
Thermal runaway possible
caused by high temp.,
environment, overcharging,
excessively high recharge
current, shorted cells, ground
fault, or a combination
Could result in the emission of
hydrogen sulfide, detectable as a
rotten egg odor, battery fire, and
inability to support the load
Replace the battery system
and correct the items leading
to the theramal runaway
condition
Rotten egg odor
Possible caused by high
temperatuare environment,
overcharging, excessively
high recharge current, shorted
cells, ground fault, or a
combination of these.
Odor is a product of thermal
runaway
Replace the battery system
and correct items leading to
thermal runaway condition
Melted grease at
terminals
Hot connections due to
excessive resistance caused
by loose connections, dirty
contact surfaces or corrosion
within connection
Excessive voltage drop •
perhaps leading to short
operating time or damaged
terminals
In extreme case could lead •
to melted terminal and
ignition of the battery cover
Clean and reassemble •
connection if damaged
Replace batteries with •
damaged terminals
Corrosion at
terminals
Possibly electrolyte leaking
from battery terminal seal
attacking the interunit
container
Increased connection resistance
and resulting increase in the
connection heating and voltage
drop at high rate discharge.
Disassemble connection,
clean, coat connecting
surfaces and terminal area,
seal with anti-oxidation
grease, reassemble the
connection. If leakage about
terminal area is obvious, the
battery should be replaced.
Table 2, Battery Symptoms and Solutions