If you first buy the battery yourself, the most correct decision taken before purchased will look into the instructions. Here you can find out, firstly, what capacity is necessary the battery, and secondly, what kind of polarity will be structurally suitable for this car.

Battery capacity (rechargeable battery) 

This value must accurately comply with the technical characteristics stated in the instructions for the car.

Units of measurement This parameter is ampere-clock.

If there is less ampere-hour in the battery, than it is written in the manual, it will quickly be discharged, the tank will not be enough even on the start of the engine and also for the normal operation of the electrical appliances.

There is an opinion that if there is more ampere-hours in the battery than it is supposed, it is very good.

But there is a disadvantage: such a battery will be constantly dissimilar, which will lead to its premature failure.

Battery polarity(rechargeable battery)

In the instruction manual, another parameter is indicated - polarity.

If you look at the battery with the front side, then with a straight polarity, the terminals should be located as follows: the left is pussy, and the right is minus.

In constructs with reverse polarity - everything is exactly the opposite: left - minus, right - plus.

On this score there is one small advice.

Auto from the United States use direct polarity, and from Japan - reverse.

The polarity scheme to a smooth account is not reflected in the characteristics of the machine and on the use of the battery.

Battery power, current power to start the engine

This criterion is very important for diesel cars, because To start the engines used in them, the power is required greater than for gasoline.

The considered characteristic shows the size of the output power of the battery in a 30-second interval at a temperature of minus 18 degrees.

The essence is simple: the higher the power, the faster the speed of rotation of the starter when the engine is started into the minus temperature.

In our case, an acceptable value will be equal to falling the battery power to 10 in 30 seconds with minus 18 degrees.

Battery dimensions(rechargeable battery)

Unfortunately, many motorists, departing for the purchase of the battery for the first time, forget about a very simple, but due to no less important characteristic - the overall size of the device.

When a quick look, under the hood of any car, the compactness of the location of all aggregates is immediately striking.

To accommodate the battery under the hood there is a special niche, the dimensions of which also need to know when buying, so that the battery fit without problems.