This will form part of our blog posts about battery chargers. There are many kinds of batteries used in the automotive field and the correct chargers must be used to charge certain batteries. In here we will outline the major battery types & specifications you need to look out for when you are deciding on a battery charger.
Basically, there are two types of lead acid batteries(along with three sub-categories).
The two main types are starting (cranking), and deep cycle (marine/golf cart). The starting battery (SLI starting lights ignition) is designed to deliver quick bursts of energy (such as starting engines) and therefore has a greater plate count. The plates are thinner and have somewhat different material composition.
The deep cycle battery has less instant energy, but greater long-term energy delivery. Deep cycle batteries have thicker plates and can survive a number of discharge cycles. Starting batteries should not be used for deep cycle applications because the thinner plates are more prone to warping and pitting when discharged. The so-called Dual Purpose Battery is a compromise between the two types of batteries, though it is better to be more specific if possible.
Wet cell(flooded), gel cell, and absorbed glass mat (AGM) are various versions of the lead-acid battery.
The wet cell comes in two styles; serviceable and maintenance free. Both are filled with electrolyte and are basically the same. I prefer one that I can add water to and check the specific gravity of the electrolyte with a hydrometer.
The gel cell and the AGM batteries are specialty batteries that typically cost twice as much as a premium wet cell. However, they store very well and do not tend to sulfate or degrade as easily as a wet cell. There is little chance of a hydrogen gas explosion or corrosion when using these batteries; they are the safest lead acid batteries you can use. Gel cell and some AGM batteries may require a special charging rate. If you want the best, most versatile type, consideration should be given to the AGM battery for applications such as Marine, RV, Solar, Audio, Power Sports and Stand-By Power just to name a few.
If you don’t use or operate your equipment daily, AGM batteries will hold their charge better than other types. If you must depend on top-notch battery performance, spend the extra money. Gel Cell batteries still are being sold, but AGM batteries are replacing them in most applications.
There is some common confusion regarding AGM batteries because different manufactures call them by different names. Some of the more common names are “sealed regulated valve,” “dry cell,” “non-spillable,” and “valve-regulated lead-acid” batteries. In most cases, AGM batteries will give greater lifespan and greater cycle life than a wet cell battery.
SPECIAL NOTE: It’s common for individuals to use the term ”gel cell” as a generic term when referring to sealed, maintenance-free batteries, much like one would use Kleenex when referring to facial tissue. As a result, be careful when specifying a gel cell battery charger, as many times we’re told by a customer that they need a charger for a gel cell battery when in fact it isn’t a gel cell at all.
AGM: The Absorbed Glass Matt construction allows the electrolyte to be suspended in close proximity with the plates active material. In theory, this enhances both the discharge and recharge efficiency. Common manufacturer applications include high-performance engine starting, power sports, deep cycle, solar and storage battery. The larger AGM batteries we sell are typically good deep cycle batteries and they deliver their best live performance if recharged before allowed to drop below the 50% discharge rate. The Scorpion motorcycle batteries we carry are a nice upgrade from your stock flooded battery, and Odyssey branded batteries are fantastic for holding their static charge over long periods of non-use. When deep cycle AGM batteries are discharged to a rate of no less than 60%, the cycle life will be 300 plus cycles.
GEL: The gel cell is similar to the AGM style because the electrolyte is suspended, but it’s different because technically the AGM battery is still considered to be a wet cell. The electrolyte in a gel cell has a silica additive that causes it to set up or stiffen. The recharge voltage on this type of cell is lower than the other styles of a lead-acid battery. This is probably the most sensitive cell in terms of adverse reactions to over-voltage charging. Gel Batteries are best used in VERY DEEP cycle application and may last a bit longer in hot weather applications. If the incorrect battery charger is used on a gel cell battery, poor performance and premature failure are certain.
CCA, CA, AH and RC standards.
These are the standards that most battery companies use to rate the output and capacity of a battery.
Cold cranking amps (CCA)is a measurement of the number of amps a battery can deliver at 0°F for 30 seconds and not drop below 7.2 volts. So a high CCA battery rating is especially important in starting battery applications, and in cold weather.This measurement is not particularly important in deep cycle batteries, though it is the most commonly “known” battery measurement.
C is cranking amps measured at 32°F. This rating is also called marine cranking amps (MCA). Hot cranking amps (HCA) is seldom used any longer but is measured at 80°F.
Reserve Capacity (RC)is a very important rating. This is the number of minutes a fully charged battery at 80°F will discharge 25 amps until the battery drops below 10.5 volts.
An amp-hour (AH)is a rating usually found on deep cycle batteries. The standard rating is an amp rating taken for 20 hours. What this means for a 100 AH rated battery is this: Draw from the battery for 20 hours, and it will provide a total of 100 amp hours. That translates to about 5 amps an hour. (5 x 20 = 100). However, it’s very important to know that the total time of discharge and load applied is not a linear relationship. As your load increases, your realized capacity decreases. This means if you discharged that same 100 AH battery by a 100 amp load, it will not give you one hour of runtime. On the contrary, the perceived capacity of the battery will be that of 64 amp hours.