Batteries are energy storage devices direct current (DC).

There are several types of batteries / battery on the market are the type of battery pack wet / conventional, hybrid and MF (Maintenance Free).

Aki wet / conventional means is still using sulfuric acid (H2SO4) in liquid form. MF battery while the battery is often referred to as dry as sulfatnya acid already in the form of gel / jelly. In terms of considering the position of the battery dry peletakkannya has no constraints, another case with the battery wet.

Conventional batteries also contain lead (Pb) is still high, about 2.5% for each positive and negative cells. While this type of hybrid content timbalnya been reduced to 1.7%, respectively, only the negative cells were added Calcium. While the MF battery / dry cell batteries still use reciprocal positive 1.7% but the negative cells are not using the lead but at 1.7% Calcium. Calcium battery acid on Sulfatnya (H2SO4) is still a liquid, only requires virtually no maintenance due to the level penguapannya very small and condensed back. Technology is now even have used silver for the mixed material negative cells.

There are several considerations in selecting the battery:

* Layout, whether upright position, tilted or upside down. If the consideration for any position then dry battery is the top choice because the battery is no liquid water will be spilled. Off road vehicles usually use dry battery recall tough terrain. Aki joined shaken and slammed. Shock-resistant battery while the battery pack dry wet materials exposed to shocks elektodanya easily fragile.
* Voltage / voltage, easily found on the market that the voltage is 6V, 12V 24V da. There is also a multipole that have a few stress points. A custom also existed, usually used for industrial purposes.
* The capacity of the battery that is written in units of Ah (Ampere hour), which states the power of the battery, how long these batteries can survive the current supply for the load / load.
* Cranking Amperes stating how big the starting current can be supplied for the first time when the load is turned on. Dry batteries usually have a smaller cranking amperage than wet batteries, but the supply voltage and the current is relatively stable and consistent. That's why many car audio devices using dry batteries.
* The use of the battery itself whether to demand or routine that is often used only as back-ups only. Aki wet, voltage and capacity will decrease when stored for long without recharge, while the battery is relatively stable when dry stored for long periods without a recharge.
* Prices for dry batteries have many advantages, the price was far more expensive than wet batteries. To bridge the price range that far then the battery manufacturers also produce a type of battery calcium (calcium battery) that cost between them.

Broadly speaking, battery differentiated based on the application and construction. Based on the battery differentiated applications for automotive, marine and deep cycle. Deep cycle battery which includes commonly used for PV (photo voltaic) and back up power. While the construction of the battery type is divided into wet, gel and AGM (Absorbed Glass Mat). Battery type usually also dubbed AGM VRLA (Valve regulated Lead Acid).

Dry Deep Cycle Battery are also designed to produce a stable and consistent voltage. Decrease in the ability of not more than 1-2% per month without needing charged. Comparing with a conventional battery could reach 2% per week for self-discharge. The consequences for charging the charging current to the battery Deep Cycle must be smaller than conventional battery so that it takes longer to fill the cargo. Between the type of gel and AGM is almost similar except that AGM batteries have all the advantages of gel-type without having deficiencies. Gel-type deficiency is charged at the time the voltage should be 20% lower than the AGM or wet-type battery. When overcharged it will arise in the cavity to be hard to repair so gelnya reduced cargo capacity.

Because there is no liquid that can freeze and expand, making the Deep Cycle battery resistant to extreme weather is freezing. That is why the extreme cold weather, vehicles that use conventional batteries can not be distart alias strike.

There are two ratings for the battery of the CCA and RC.

* CCA (cold cranking ampere) indicates how much current that can be issued simultaneously for 30 seconds at the freezing point of water is 0 degrees Celsius.

* RC (Reserve Capacity) shows how long (in minutes) battery can deliver currents of 25A while keeping its voltage above 10.5 Volts.

Deep Cycle batteries have 2-3 times the RC value than a conventional battery. AGM battery ages average between 5-8 years.