t began building gel cell batteries using tried
and true technology backed by more than 50 years experience.
Our unique computer-aided manufacturing expertise and vertical
integration have created a product that is recognized as the highest
quality, longest life gel battery available from any source.
Applications
Gel cells can be used in virtually any flooded electrolyte wet cell
application (in conjunction with well-regulated charging), as well as
applications where traditional wet cells cannot be used. Because of
their unique features and benefits, gel cells are particularly well
suited for:
Deep Cycle, Deep Discharge Applications
Marine Trolling
Electronics
RVs
Electric Vehicles
Wheelchairs
Sailboats
Portable Power
Floor Scrubbers
Golf Cars
Personnel Carriers
Marine House Power
Commercial Deep Cycle Applications
Standby and Emergency Backup Applications
UPS (Uninterrupted Power Systems)
Emergency Lighting
Computer Backup
Cable TV
Telephone Switching
Unusual and Demanding Applications
Race Cars
Air-transported Equipment
Off-road Vehicles
Wet Environments
Marine Starting
Diesel & I.C.E. Starting
What is a gel cell?
A gel cell is a lead-acid electric storage battery that:
is pressurized and sealed using special valves, and therefore
should never be opened.
is completely maintenance-free*.
uses a thixotropic gelled electrolyte.
uses the recombination technique to replace oxygen and
hydrogen normally lost in a wet cell (particularly in deep
cycle applications).
is non-spillable, and therefore can be operated in virtually
any position. However, installation upside-down is not
recommended.
* Connections must be retorqued and the batteries should be cleaned periodically.
How does a gel cell work?
A gel cell is a recombinant battery. This means that the oxygen
that is normally produced on the positive plate in all lead-acid
batteries recombines with the hydrogen given off by the negative
plate. The recombination of hydrogen and oxygen produces
water (H
2
O), which replaces the moisture in the battery. Therefore,
the battery is maintenance-free, as it never needs watering.
The oxygen is trapped in the cell by special pressurized sealing
vents. It travels to the negative plate through tiny fissures or cracks
in the gelled electrolyte.
The sealing vent is critical to the performance of the gel cell.
The cell must maintain a positive internal pressure. Otherwise the
recombination of the gasses will not take place, and the cell will
dry out and not perform.
In addition, the valve must safely release any excess pressure that
may be produced during overcharging. Otherwise the cell would be
irreparably damaged.
Its important to note that a gel cell must never be opened once
it leaves the factory. If opened, the cell loses its pressure, and the
outside air will poison the plates and cause an imbalance that
destroys the recombination chemistry.
Hence the name: Sealed Valve Regulated (SVR) Battery.
What is the difference between gel
cell and starved electrolyte batteries?
Both are recombinant batteries; both are sealed valve regulated.
The major difference is that the starved or absorbed electrolyte
battery contains an amount of liquid electrolyte added at the factory
that soaks into the special separators. Therefore, it is non-spillable
because all the liquid electrolyte is trapped in the sponge-like
separator material. There is no free electrolyte to spill if tipped
or punctured.
Because of this acid-starved condition, this type of battery does
not normally perform well in heavy, deep discharge applications.
The gel cell has more electrolyte available, therefore it is better
suited for deep discharge applications and can accept occasional
overcharging.
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What is the difference between
gel cell and traditional wet batteries?
Wet cells do not have special pressurized sealing vents, as they do
not work on the recombination principle. They contain liquid elec-
trolyte that can cause corrosion and spill if tipped or punctured.
Therefore, they are not air transportable without special containers.
They cannot be shipped via UPS or Parcel Post or used near
sensitive electronic equipment. They can only be installed upright.
Wet cells lose capacity and become permanently damaged if:
left in a discharged condition for any length of time (due to
sulfation). This is especially true of antimony and hybrid types.
continually over-discharged, due to active material shedding.
This includes specially designed deep cycle wet cells,
but is especially true of automotive types.
Deep cycle antimony wet cells have seven times less shelf life as well.
Our gel cells have triple the deep cycle life of wet cell antimony alloy
deep cycle batteries, due to our unique design.
How do gel cells recharge?
Are there any special precautions?
While our gel cell will accept a charge extremely well due to its
low internal resistance, any battery will be damaged by continual
under- or overcharging. Capacity is reduced and life is shortened.
Overcharging is especially harmful to gel cells because of their
sealed design. Overcharging dries out the electrolyte by driving the
oxygen and hydrogen out of the battery through the safety valves.
Performance and life are reduced.
If a battery is continually undercharged, a power-robbing layer of
sulfate will build up on the positive plate, which acts as a barrier
to electron flow. Premature plate shedding can also occur.
Performance is reduced and life is shortened.
Therefore, it is critical that a charger be used that limits voltage
to no more than 14.1 volts and no less than 13.8 volts at 68°F.
Batteries used in float service should be charged at 13.8 volts.
For deep cycle service, a maximum voltage of 14.1 should be used.
The charger must be temperature corrected to prevent under- or
overcharging due to ambient temperature changes. (See Charging
Voltage vs. Ambient Temperature chart on page 11.)
Important Charging Instructions
The warranty is void if improperly charged. Use a good constant
potential, temperature corrected, voltage-regulated charger.
Charge gel cells to at least 13.8 volts but no more than 14.1 volts
at 68°F (20°C). Constant current chargers should never be used
on gel cell batteries.
Can gel cells be installed in
sealed battery boxes?
NO! Never install any type of battery in a completely sealed
container. Although the normal gasses (oxygen and hydrogen)
produced in a gel cell battery will be recombined as described above,
and not escape, oxygen and hydrogen will escape from the battery
in an overcharge condition (as is typical of any type battery).
For safetys sake, these potentially explosive gasses must be
allowed to vent to the atmosphere and must never be trapped in
a hermetically sealed battery box or tightly enclosed space!
Can our gel cell be used as
a starting battery as well?
Our gel cell will work in SLI (Starting, Lighting and Ignition)
applications providing the voltage is regulated between 13.8 and
14.1 volts at 68°F. Most vehicles regulators are set higher than
14.1 volts. Therefore, the charging system must be adjusted for the
battery to recharge properly for best performance and longest life.
What do the ratings and specifications
signify for this line?
All ratings are after 15 cycles and conform to BCI specifications.
CCA = Cold Cranking Amps at 0°F (17.8°C)
Cold cranking amps equal the number of amps of current a new,
fully charged battery will deliver at 0°F (17.8°C) for thirty seconds
of discharge and maintain at least 1.2 volts per cell (7.2 volts for
a 12-volt battery).
CA = Cranking Amps at 32°F (0°C)
Same as above, tested at 32°F (0°C). (Note: All cranking ratings
are guidelines. Gel batteries are designed for cycling foremost.)
RC = Reserve Capacity at 80°F (27°C)
The reserve capacity is the time in minutes that a new, fully charged
battery can be continuously discharged at 25 amps of current and
maintain at least 1.75 volts per cell (10.5 volts for a 12-volt battery).
Minutes discharged at 50, 25, 15, 8 and 5 Amps
Minutes discharged is the time in minutes that a new, fully charged
battery will deliver at various amps of current and maintain at least
1.75 volts per cell. These are nominal or average ratings.
Ampere Hour Capacity at 20, 6, 3 and 1 Hour Rates
Ampere hour capacity is a unit of measure that is calculated by
multiplying the current in amperes (amps) by the time in hours
of discharge to 1.75 volts per cell. (These are nominal or average
ratings.)
EXAMPLE
10 amps for 20 hr. (10 x 20) = 200 Ah @ 20 hr. rate
8 amps for 3 hr. (8 x 3) = 24 Ah @ 3 hr. rate
30 amps for 1 hr. (30 x 1) = 30 Ah @ 1 hr. rate
Therefore, if you have an application that requires
a draw of 17 amps for 3 hours, you would need
a 51 Ah battery (@ 3 hr. rate)(17 x 3 = 51).
However, the 51 amp hours delivered is
100% of the capacity of this 51 Ah battery.
Most system designs will specify a battery that will deliver a
minimum of twice the power required. This means the battery
will discharge to 50% of its capacity. Using a 50% depth of
discharge (versus 80% or 100%) will dramatically extend the life
of any battery. Therefore, when helping to specify a battery for a
system, choose a battery with twice the capacity required for best
performance. If 50 Ah is required, specify at least a 100 Ah
battery.
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CHART A
Independent Laboratory B.C.I.
E.V. Life Testing
MK Gel 27 vs. Competitive 27
Sealed Valve Regulated (Gel & AGM)
This chart demonstrates the superior
cy