There are four main safety hazards associated with the use of any valve regulated lead acid
(VRLA) battery. These hazards are: a) Release of ignitable gas, b) Exposure to acid, c)
Shorting of terminals, d) Thermal runaway. This chapter provides a description of each of these
hazards and means to mitigate them.
1 Release of Ignitable Gasses
All lead acid batteries, including VRLA batteries, produce hydrogen and oxygen gases during
normal charging. Even though VRLA batteries are designed to recombine these gases
internally, the recombination efficiency is less than 100%. Small amounts of hydrogen and
oxygen are released from the pressure relief valve during charging. Normally, the hydrogen gas
dissipates very rapidly and never reaches a concentration level that is hazardous. However, if
the battery is installed in an enclosure with minimal airflow, the concentration of hydrogen could
build up to a high enough concentration to be of concern. Hydrogen can ignite at
concentrations as low as 4% in air. For this reason, never install a Lifeline® AGM battery in
a sealed or an airtight container.
2 Exposure to Acid
All lead acid batteries contain sulfuric acid in the electrolyte, which can cause chemical burns to
body tissue. Although Lifeline® AGM batteries are classified as Nonspillable, exposure to the
electrolyte is possible under extreme conditions (e.g., if the battery is cracked open or crushed).
In the event that electrolyte is displaced from the battery, avoid contact with the skin,
eyes and clothing. In the event of an accident, flush with water and call a physician
3 Shorting of Terminals
Lifeline® AGM batteries have very low internal impedance and therefore are capable of
delivering high currents if the external terminals are short circuited. The resulting heat can
cause severe burns and is a potential fire hazard. Accidentally placing metal objects across the
terminals can result in severe skin burns. It is a good practice to remove all metallic items
such as watches, bracelets and rings when installing or servicing batteries. As a further
precaution, insulating gloves should be worn and only insulated tools should be used
when installing or servicing batteries.
4 Thermal Runaway
Thermal runaway is a condition in which the battery temperature increases rapidly resulting in
extreme overheating of the battery. Under rare conditions, the battery can melt, catch on fire, or
even explode. Thermal runaway can only occur if the battery is at high ambient temperature
and/or the charging voltage is set too high. As the battery accepts current, its internal
temperature rises. The rise in temperature reduces the battery impedance, causing it to accept
more current. The higher current further heats the battery, and so on, causing the battery
temperature to “runaway”. An upper limit will eventually be reached when the electrolyte starts
to boil, but once the electrolyte has boiled away, the temperature can climb even further to the
point of plastic meltdown and possible fire.
As of this writing, Concorde does not know of any Lifeline® AGM batteries that have failed due
to thermal runaway. To preclude the possibility of thermal runway, the battery charging
instructions here should be carefully followed, especially if the battery will be
subjected to high ambient temperatures. Batteries should not be installed near heat
sources or in direct sunlight that may artificially elevate their temperature. Also, there
should be adequate air circulation around the batteries to prevent heat build-up.
BD Batteries - A Broomfield-Designers Company
Serving the Local Colorado Community 9-5 Mountain & Emergencies P. 303-800-4725 F. 303-600-9726
Serving the Buffalo and the Great Lakes Communities 9-5 Eastern & Emergencies P. 716-531-4875
Mailing Address: 5023 West 120th Ave. #138, Broomfield, CO 80020
OUR DENVER WAREHOUSE IS MOVING TO A NEW LOCATION AT THIS TIME.
WE WERE SCHEDULED TO REOPEN OUR BRICK AND MORTAR BATTERY WAREHOUSE IN EARLY 2011.
IN THE MEAN TIME OUR WEBSITE AND PHONES OPERATE FINE!
We do thank the public for the outreach of concern, and votes of confidence.
Do call Lorene prior to schedule used battery pickups, new battery dropoffs, etc. by appointment.
The information contain on this deep cycle AGM batteries website is deemed reliable, but not guaranteed. Please verify specific information on marine AGM batteries, rv AGM batteries or auto AGM batteries listed here by calling us direct. We are proud to offer the highest quality AGM batteries and hope you will consider using our deep cycle AGM batteries in the near future!