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A while ago my car battery was flat & I had to call AA roadside service to jump start the vehicle. While the technician was there I mentioned that I'm considering buying a battery charger, and he reminded me that the AA battery in my car is silver calcium so I should look for a charger that's compatible with silver calcium batteries. I've tried looking on Google & TradeMe but couldn't find any battery chargers that specifies it works with silver calcium batteries. Can you please recommend one that does the job (for home garage use) and not too expensive? Thanks in advance.

Technically the roadservice officer gave you the correct information. A charger specifically designed for a calcium maintenance free battery is the only way to guarantee the battery will reach a full state of charge.

Don’t be afraid however to use a standard battery charger as no harm will be done. The downside is the battery may only ever reach a 75% state of charge. This, according to our good friends at AA Batteries, is because there is a acid/water separation in a calcium battery when it goes dead flat. The way the specific calcium battery charger works is; it allows a higher voltage to enter the battery in the final stage of the charge cycle.

The need to use this type of charger is only critical when the battery has gone completely flat to be honest.

Once a battery has been charged with a conventional charger a visit to an auto electrician will very quickly provide an answer to the batteries overall condition.

My understanding is Repco stores sell a specific calcium battery charger.

What has become very popular of late is a unit called a battery stabiliser/charge maintainer. Ideal for those who park their cars up for a long periods or don’t use their cars on a regular basis, these units simply maintain a batteries charge to stop them going flat. Most auto electricians will sell a version of these charges or you can call the AA Breakdown number to enquire about purchasing direct (0800 500 222).