Battery Chargers -Light Your Fire
by The Vette Nut's

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.


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.