The so-called AGM battery allows, according to the battery manufacturer Banner, more flexible and broader energy management in the vehicle. It is used, among other things, in cars with start-stop systems and is easy to retrofit in any motor vehicle.
AGM stands for “Absorbent Glass Mat” and the use of glass fleece mats in the battery construction. With an AGM battery, the individual cell elements are pressed into the battery before installation. This reduces sludge. The high packing density reduces the internal resistance, which improves the cold starting properties. Extremely high vibration resistance and cycle stability are further advantages of this design. Even deep discharges can handle the AGM battery well, resulting in three times longer cycle life than conventional lead-acid batteries.
The Best AGM battery can be placed upside down without losing a drop of liquid as a highly porous fleece mat of glass microfibers (AGM) completely absorbs and binds the electrolyte fluid. Besides, the wholly sealed housing comes with a pressure relief valve. The recombination technology ensures that the gas produced during the charge is converted to water – recombined – becomes. In typical operation, no loss of water occurs. Even with a damaged case, nothing can leak, which makes the battery maintenance-free.
Series use at BMW
Due to its higher performance compared to conventional batteries, the AGM version is suitable for the following applications:
- High-energy vehicles such as luxury cars, taxis and rescue vehicles,
- Car with start-stop system,
- subsequently upgraded cars with high power requirements due to the sound system such as TV or telecommunications or a heater.
Since 2007, Banner supplies the carmaker BMW with a 90 Ah AGM battery for a standard installation in the BMW 1 Series and 3 Series with Start-Stop system.
When retrofitting such an AGM battery in the vehicle, only the following points must be considered:
- The maximum charging voltage must not exceed 14.8 volts. For this, the workshop must check the design of the generator in the vehicle. To charge the AGM battery, use only voltage-regulated, external chargers with IU characteristics and an “AGM or GEL” charge program.
- Never open the screw connections of an AGM battery. Because the electrolyte is bound in the glass fleece, no battery water needs to be refilled. However, opening the AGM battery may cause an imbalance in oxygen/hydrogen ratio and performance degradation.