The automotive battery is the power source that drives
every energy consuming component in an automotive system. A poorly
maintained, underpowered power source will cause modern and older
automotive systems to exhibit both drivability and reliability
problems. Most of us gear heads take the battery in our cars for
granted. We do not usually pay much attention to our trusty old battery
until it fails. This lack of concern is due in part to the reliability
of the modern car battery.
Automotive batteries provide a nominal
12-volt potential difference by connecting six galvanic cells in
series. Each cell provides 2.1 volts for a total of 12.6 volt at full
charge. Lead-acid batteries are made up of plates of lead and separate
plates of lead dioxide, which are submerged into an electrolyte
solution of about 35% sulfuric acid and 65% water. This causes a
chemical reaction that releases electrons, allowing them to flow
through conductors to produce electricity. As the battery discharges,
the acid of the electrolyte reacts with the materials of the plates,
changing their surface to lead sulfate. When the battery is recharged,
the chemical reaction is reversed: the lead sulfate reforms into lead
oxide and lead. With the plates restored to their original condition,
the process may now be repeated.
In normal automotive service the vehicle's engine-driven alternator
powers the vehicle's electrical systems and restores charge used from
the battery during engine cranking. When installing a new battery or
recharging a battery that has been accidentally discharged completely,
one of several different methods can be used to charge it. The most
gentle of these is called trickle charging. Other methods include
slow-charging and quick-charging, the latter being the harshest.
Some manufacturers include a built-in
hydrometer to show the state of charge of the battery. This acrylic
"eye" has a float immersed in the electrolyte. When the battery is
charged, the specific gravity of the electrolyte increases (since all
the sulfate ions are in the electrolyte, not combined with the plates),
and the colored top of the float is visible in the window.
When the battery is discharged (or if
the electrolyte level is too low), the float sinks and the window
appears yellow (or black). The built-in hydrometer only checks the
state of charge of one cell and will not show faults in the other
cells. In a non-sealed battery each of the cells can be checked with a
portable or hand-held hydrometer. Batteries will last longer if not
stored in a discharged state.
Sulfation occurs when a battery is not fully charged, and the longer it
remains in a discharged state the harder it is to overcome the
sulfation. This may be overcome with slow, low-current (trickle)
charging. Sulfation is due to formation of large, non-conductive lead
sulfate crystals on the plates; lead sulfate formation is part of each
cycle, but in the discharged condition the crystals become large and
block passage of current through the electrolyte.
Ok now that we have somewhat of a handle on the basics we can come up
with some simple solutions to your lack of attention to this very
important component in the automotive system. If your special ride is a
garage or trailer queen it is probably hidden away in the garage under
a protective cocoon. Lack of exercise and long storage periods will
cause the best of batteries to loose most of their oomph. Unless you
enjoy replacing batteries on a regular basis you need to find a way to
rejuvenate that power box.
CTEK
Battery charger
The MULTI US 3300 is a versatile and compact battery
charger designed to easily charge and maintain all types of vehicles
batteries including Optima gel type batteries. The charger features a
special cold mode that enables you to charge a battery during cold
winters days without problems.
The MULTI US 3300 has a water resistant
and weatherproof design that enables its use in damp environments. In
our test we hooked up the multi 3300 to a discharged 650 amp marine
battery starting battery. The hookup was easy, red alligator clip to
positive terminal and black alligator clip to negative terminal. No
rocket science here.
The battery initially measured 12.2
volts, after about 12 hours of charging a fully charged indicator light
was displayed on the unit. We liked the chargers small size, simplicity
and weather resistant design. The only trade off is the long charging
time. The unit is manufactured in Sweden and is priced at about $115.
Save-a-Battery
The Save-a-Battery is a fast, 50-watt 2x Battery
charger. After charging the unit then automatically switches to
maintenance/monitoring mode. By varying current and voltage in a deeper
cycle, it desulfinates a battery, and extends its life without
overcharging. A low voltage alarm monitors the battery and sounds
before damage occurs from discharging.
The manufacturer claims that you can
leave the unit permanently connected, with no risk of overcharging. A
built in voltmeter also lets you test your wiring and charging system.
the large LCD screen and bright LED bank make it easy to monitor
battery voltage, charging mode, connection status, and overall battery
health. The LCD display can be turned off while charging or maintaining
for long-term storage.
The unit is equipped with modular
plug-in cables with three types of battery connectors. The charger
comes with a 10' foot long AC power cord; and gold-plated connectors
for reliability in damp garages and boathouses. The "No-sparks"
polarity protection prevents operation if you screw up the connection
to your battery.
The Save A Battery 12-Volt Battery Charger Maintainer
and Tester comes with a 6-foot 5-Amp battery terminal lug cable, a
6-foot alligator clip cable, a 6-foot cigarette lighter adapter cable,
a 10-foot AC power input cable, and a mounting bracket for permanent
wall or vehicle installation.
We set up our test on a 750amp starting battery that resided in the
engine bay of a C5 Corvette. The battery was in a state of severe drain
from under use and was due for replacement. We connected the Save a
Battery unit as per the instruction manual. The LCD read out measured
12.2 volts at startup.
To our surprise the unit recharged the
battery in less than two hours. This rivaled the performance of much
larger chargers. Guess what we don't need to replace the battery
anymore. This magic box seems to have brought the old battery back to
life. We give this product a definite thumbs up, it is reasonably
priced at about $99
Battery
Tender Plus
The Battery Tender Plus battery charger delivers 1.25
amperes during bulk charge mode, holds the battery charge voltage
constant at 14.4 VDC during absorption charge mode until the battery
charge current drops to 0.1 amperes at which time it then automatically
switches to a float charge mode.
During float charge mode, the output
voltage of the Battery Tender Plus battery charger is 13.2 VDC, which
is well below the gassing voltage of a lead acid battery. This keeps
the battery topped off, while minimizing any detrimental effects to do
gassing. The Battery Tender Plus battery charger is able to perform
these complex switching functions because its electronic circuitry is
controlled by an on board microprocessor.
We tested the unit on a partially discharged lead acid battery that was
few years old. The unit was connected in a similar fashion to the other
chargers. Once plugged in the a flashing red led came on indicating
that power was on. Once connected to the battery the red light stopped
flashing indicating that the battery was being charged. After charging
is complete a green led is supposed to intermittently flash. We left
the charger on for approximately 12 hours and never got a green light
indication. Our initial reaction was that the battery was defective. We
attempted to charge another battery that we knew was in perfect shape.
Again after about ten hours of charging no green flashing light.
We called the Deltran Corporation and were told that the unit probably
needed to recycle itself. We were told that this process could take up
to 72 hours. We are still waiting for our green flashing light to come
on.