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Cold-cranking amperes or CCA is
unit of measurement that generally determines a battery's ability to start your engine. CCA is a measurement of
worst conditions under which a battery can be expected to deliver current, and it tests how much current in amperes a battery can deliver under extreme cold. According to
American SAE standard, CCA is determined by measuring how much current can be delivered in amperes for 30 seconds at -18 degrees C with a final voltage of 7.2 volts per cell or higher.
Reserve capacity is an important measurement for
total capacity of
battery and shows how long a battery can keep
engine running if
alternator/generator fails. Reserve capacity of a battery is measured in minutes at room temperature (approximately 70 degrees F). During this test, 25 amperes is drawn from
battery for as long as
voltage does not drop below 10.5 volts. For off-road use, it's a good idea to make sure any battery you purchase has a reserve capacity of at least 120 minutes.
Reserve capacity is also important for those times when you need to run a radio, spotlight, winch, or other electrical accessory without running
engine.
A Batteries Two Enemies
Although just about all modem batteries are pretty reliable, there are two enemies that can grind even a brand-new battery to a halt - extreme cold and extreme heat. Batteries are at their best with internal temperatures (not ambient) above 50 degrees F and below 105 degrees F. Below and above this range, problems can develop, and a dead, damaged, or . useless battery can be
result.
We've all noticed that under extremely cold conditions (below freezing),
battery will turn over
starter motor slowly, if at all. This is because when
internal temperature of
battery gets below
optimum range,
chemical reaction inside
battery happens more slowly, and for every 10-degree drop below freezing,
time that
chemical reaction takes doubles. Because of this increased resistance,
voltage in
battery drops and cannot turn over
engine.
Heat can also have an adverse effect on your battery's overall health. Battery power is reduced when it's subjected to excessive temperatures, but
problem may not be immediately noticed until
temperature drops. At higher temperatures,
chemical reaction within
battery is more rapid. The battery can produce more energy more quickly. This is good, right? Wrong. The higher rate of energy production results in an increase in off gassing;
water in
battery is vented out as hydrogen and oxygen molecules and
rate of internal corrosion, or sloughing, increases. This can result in a short in one or more cells that is not noticed until cold weather diminishes
overall ability of
battery.
What to Buy
When it comes to batteries for automotive use, there is no such thing as a perfect battery. Any battery can fail if it is neglected, constantly overloaded, or overcharged. The important thing to remember is to get
right battery for your needs, one that is rated for your vehicle and all
accessories you use. Generally, this means a high Ah, high CCA, and high reserve capacity. Also, make sure you buy a quality unit. Don't be fooled by
low price of
budget shops. Batteries sold in
no-name-battery discount stores often are poorly assembled and use inferior materials in
plates and separators. Name-brand batteries, such as AC-Delco, Sears DieHard, Exide, Interstate, Optima, and others, are manufactured to
highest standards, delivering high reliability combined with long life.
For off-road use, however, we feel that
recombination battery is
best overall, since it delivers high output, needs no maintenance, holds up well to
rigors of off-road driving, and has a quick recharge rate, as well as a long life span. It is a particularly useful battery for
off-roader because it has no liquid to leak out and can be mounted in any position (even upside down). Because of this, it won't corrode battery trays or cables and is safe in a collision. You can actually shoot a 45-caliber bullet through
battery casing and it will still crank at full power. Try that with a conventional battery, and you have a leaking mess that will at best produce minimal voltage.
Although recombination batteries are sold under various brand names, Optima's 800U is
original and also
only battery available with both top posts and side terminals, a feature that makes it especially well suited for specialized installations and powering accessories and where there is installation room for only one battery Since we also run a winch and driving lights from
starting battery, it has to be a powerful one. The 800 CCA and 120 minutes of reserve capacity
Optima offers means we can rely on
unit as a power source for lights and winch use when
engine is down, without sacrificing starting ability. Additionally,
side terminals make it easy to power
winch and other accessories directly off
battery without disconnecting
main power cables and disabling
vehicle's computer. This makes for a clean installation without a lot of cable clutter at
main battery posts, which is especially important when there's limited space around
battery top.

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