The common type of battery is some form of lead battery. 

There are other types, such as nickel-cadmium and nickel-metal hybrid, but they are uncommon and are not described below. 

 

A lead battery consists of a number of serially-connected battery cells. Each cell delivers a nominal voltage of two volts. 

Normally there are six cells in every (car) battery, which thus deliver a nominal voltage of 12 volts. If two 12-volt batteries are serially connected a voltage of 24 volts is achieved. Six-volt batteries with 3 cells also exist and in their case four batteries are needed to generate 24 volts. 

In the truck business, individual battery cells of 2 volts each are used, placed in a steel basket and then connected to each other, and in this way truck batteries for different voltages and capacities are built. 

 

In the lead battery, electrical energy is stored chemically in the plates of the battery cells. 

The size and number of the plates determines the capacity of the battery. 

Capacity is stated in ampère hours (Ah). A common size is 60 ampère hours, which means that a fully-charged new battery can deliver 12 ampères for 5 hours. If two batteries are serially connected, they must have the same ampère hour value and they should be of the same type and age for the charge to work best. In a lead battery, besides the active plates, there is also a fluid (electrolyte), which consists of diluted sulphuric acid. 

 

Today, batteries are normally either enclosed, where the electrolyte has been absorbed by a porous mat or made to gel into a gelatinous mass, or of the conventional open type. Enclosed batteries are also called valve-regulated or maintenance-free batteries and normally require no maintenance. 

Open batteries, however, need to be kept filled with battery water in order not to dry out; how often and how much depends to a large extent on usage, but also on the choice of battery charger. 

 

During discharge, lead sulphate forms on the lead plates of the battery, and lead sulphate reduces the capacity of the battery, which is why a lead battery should always be charged when stored, preferably with some kind of trickle charge. 

Crystalline lead sulphate can to some degree be dissolved by a properly dimensioned top charge or trickle charge. 

 

So much lead sulphate forms during deep-charging that the battery is subjected to such mechanical stress that service life is shortened. 

Always try, therefore, to avoid emptying the battery entirely; if you feel you risk deep-charging the battery, it is always better to use intermittent charging. 

 

If you suspect that the battery is becoming sulphated, the most effective way to deal with that problem is to charge the battery using weak current over an extended period of time, 0.8 – 1% of the battery’s capacity (Ah). 

A 600 ampère hour (Ah) battery should be charged with 5 – 6 ampères for at least a week, or preferably 2 – 3 weeks. 

Many batteries have been unnecessarily discarded due to sulphation that could be remedied this way, depending of course on how severely sulphated the battery is. 

 

 

The charger transforms alternating current from the mains to direct current, which then, with the aid of advanced electronics, is regulated and then charged into the battery. The battery charger is to quickly give a complete charge, but not deliver more current than the battery can withstand during the different phases of charging. This is controlled by the programmed charging curve stored in the charger’s microcomputer. 

Thus, it is important that the charger has the correct charging curve for each type of battery, or there is a risk of ruining the battery by either undercharging or overcharging.

 

Together with battery manufacturers we have produced efficient charging curves that handle maintenance optimally and charge the battery as fast as it can handle without being damaged. A charging curve primarily contains three charging phases: main charge, top charge and trickle charge. During actual main charging, the energy drawn out of the battery is basically replaced. During top charging, overcharging of approx. 15% occurs, in order to achieve an equalisation of the charge between the cells of the battery. In valve-regulated batteries, top charging is only done with weak current, in order to prevent hydrogen from forming and overpressure from forming in the battery, which in turn results in the valves opening and releasing some gas, which eventually results in the battery drying out and being ruined. 

The charger must not supply too much current to the battery, as this may overheat it, damaging the battery. 

Trickle charging compensates for the battery’s self-discharge. 

 

For the charger to take care of the battery properly, it must be adapted to each battery type and be of the right size (ampères). All of Micropower’s chargers adapt individually to each battery, in order to get the most out of every battery. 

The chargers come in different sizes so that the correct charging time is used. 

 

Since almost all batteries need to be handled differently, we cannot in general terms say how long the charging time should be, but we will give an example with a common battery. 

 

A freely ventilated 600 Ah battery that is 80% discharged will take over 8 hours to charge fully with a 125A Wa charger (STC) or an 80A regulated charger with chemical acid stirring (MTM, MTM-HF). 

 

 

Never deep-discharge the battery; charge intermittently as necessary. 

Discharge max. 60-80% with valve-regulated batteries (maintenance-free). 

When sulphating has occurred, equalise charge at least once a week by letting the charger remain connected for an extra long time. 

Do not subject the battery to extreme temperatures; allow the battery to rest between use and charging. 

Micropower’s modern chargers read the condition of the battery and adapt the entire charging process to the battery. 

Should you connect a newly-charged battery to the charger, Micropower’s chargers will automatically switch to trickle charge. 

Micropower’s chargers will charge and handle the battery the best way possible every time, to ensure maximum life and capacity.