Which Battery Charger Is Right For You?
Choosing a battery charger used to be easy - get the biggest and heaviest you can find! That was fine when automotive batteries had to be checked every week and topped up, and they lasted about a year, two if you were really lucky.
Today’s batteries are a different animal, they are smaller, lighter, more powerful and you don’t need to top them up, and with luck they will last for up to five years. This change in technology has meant that the charger has had to develop too.
Different battery types require different charging routines to ensure that the battery is correctly and fully charged, with the sophisticated electronics now on all vehicles a fault with the battery can cause all sorts of problems.
There are two main types of battery technology fitted to vehicles:
Calcium/Calcium or Calcium/Silver type is used as a starter battery, and on single battery vehicles this is the type fitted. AGM or Absorbed Glass Matt, on vehicles fitted with two batteries (and there are more than you think) this is the battery that powers the systems other than the engine related systems.
Both these battery types require different charging methods if they are to be correctly charged, putting high current into a Calcium battery can damage it and be potentially dangerous, where an AGM type is more able to accept a higher charge.
So to sum up the ‘one type fits all’ and ‘the bigger the better’ approach to battery charging is no longer acceptable as delicate electronics and humans can suffer unless the correct procedure is followed.
Each one of our charger models carries a description of the battery types it is suitable for.
WHAT IS SULPHATION?
Batteries have a finite life and cannot be expected to last forever, however it is possible to increase the life expectancy of the battery by following a few simple rules.
During the normal discharge process, the sulphuric acid in the electrolyte reacts with the lead plate material to produce soft lead sulphate crystals in the pores, and on the surfaces of the positive and negative plates inside a lead-acid battery. When a battery is left in a discharged condition, continually undercharged, or the electrolyte level is below the top of the plates, some of the soft lead sulphate re-crystallizes into hard lead sulphate. The hard lead sulphate cannot be reconverted during subsequent recharging process. This creation of hard crystals is commonly called permanent "sulphation". It accounts for approximately 85% of the lead-acid battery failures that are not used weekly. The longer period over which sulphation occurs, the larger and harder the lead sulphate crystals become. The positive plates will be light brown and the negative plates will be dull, off white colour. These crystals lessen a battery's power capacity and ability to be recharged. How the battery is used is important; this is because deep cycle and some starting batteries are typically used for short periods, vacations, weekend trips, etc., and are then stored the rest of the year to slowly self-discharge causing sulphation. Car batteries are normally used several times a month, so sulphation rarely becomes a problem provided the car is in regular use.
HOW CAN I TELL IF MY BATTERY IS SULPHATED?
Chances are that your battery has some permanent sulphation, if it exhibits one or more of the following conditions:
If your wet Standard (Sb/Sb)* or wet Low Maintenance (Sb/Ca) battery has been not been echarged for over three months, especially if the storage area was warm or hot. (Six months for wet Maintenance Free (Ca/Ca) or one year for VRLA AGM or Gel Cell.) If the temperature compensated absorption charging voltage is correct and the battery is gassing excessively. Poor performance, or it will not hold a charge.
