How Does it Work / Car Battery

• Battery Questions and Answers

Car Battery

A car battery is a rechargeable cell in the SLI (starting-lighting-ignition) variety of batteries. They are also in the lead acid family of batteries. Lead acid batteries are the oldest style of rechargeable batteries. The high power output of a car battery is necessary to supply a high current draw needed for the engine starter. A normal car battery provides about 12.6 volts and is divided into 6 separate cells, each cell produces about 2.1 volts per cell. As the battery state of charge decreases the voltage produced also decreases.

Delco Car Battery

Battery power is created through a chemical reaction. Inside your battery there are positive and negative lead plates that are immersed in an electrolyte solution (battery acid). This solution is a combination of water and sulfuric acid. When the solution interacts with the lead plates, the chemical interaction creates voltage. This voltage is then released through the battery�s positive terminal (red) and returned to the negative terminal (black). Voltage from the alternator maintains the battery state of charge. This continuous cycle can produce electricity for years.

When the battery is overcharged or jump started, water in the electrolyte solution is transformed into hydrogen and oxygen. This can cause an explosion from the battery if a spark or an other source of ignition is present. It also decreases the fluid level inside the battery and can expose the lead plates. Exposure to oxygen can damage these plates and reduces their ability to provide the chemical reaction needed. Inspect your battery regularly, if acid is present replace the battery and check the charging system.

Be extremely careful when handling a car battery, gloves and eye protection are recommended as battery acid is highly corrosive. When charging a battery use caution, always connect the charge leads while the charger is off. This will prevent a spark from being created, a battery is most prone to an explosion after a battery charge. The most common way to recharge your battery is by a process called trickle charging. This is performed using a inexpensive trickle charger, most repair shops have a more powerful and more expensive battery charger that is capable of charging at a higher rate.

To jump start a car, a set of jumper cables is needed. Attach the discharged battery to a battery of a running vehicle, connect the positive cable first, then connect the negative cable to a good ground source (ex: engine accessory bracket) last to avoid sparks. The jumper cables are usually color coordinated to match the positive and negative terminals on a battery. It is important to match the terminal via the cables on the respective batteries. It should match positive to positive and negative to negative. Reversing these cables will result an undesirable electrical event.

When replacing a battery be sure to wear gloves, protective goggles and long sleeve clothing then follow these steps: First, remove the ground connection or negative connection, then remove the positive. This will reduce the chance of a short while disconnecting the positive cable. Next, remove the battery hold down mount, reverse this order to reinstall. After installation is complete recheck the charging system.

Maintaining a car's battery is a necessary step in any vehicle's preventative maintenance and should be checked regularly.

Clean Battery and Terminals - There are deposits that can form on the battery terminals. These deposits are corrosive by-products of a normal battery charge and discharge function. While wearing protective goggles and clothing, use a garden hose to rinse the battery completely also rinse the surrounding area, this will dilute the acid to a non-corrosive state. You can also sprinkle baking soda to help neutralize the battery acid. Use a wire brush on the battery terminals to clean thoroughly and reassemble, recheck charging system as needed.

Battery Storage

Replace Battery Cables - If excessive corrosion on battery cables are observed they should be replaced. Corrosion can cause high resistance resulting in a starter operation failure. Avoid using after market cables as they may not be manufactured to proper specifications resulting in poor battery performance.

Recycling Old Batteries - An old car battery is completely recyclable, contact your local recycling station, auto part store or repair garage. Do not discard an old battery in a land fill or the back of your garage.

How Does it Work / Car Battery

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