Battery Chargers On Test

November 2007

Today’s gadget-packed cars have made owning a battery charger more necessary than ever. Even if your vehicle is parked on the street or in your garage, its immobiliser and other security kit can drain the powerpack round the clock. Batteries have changed to meet the new demands – and so have chargers. Older, less sophisticated designs could damage modern powerpacks, which are less tolerant of overcharging and the resulting ‘gassing’ of the cells.

The latest products are designed to solve these problems. Most can tackle deeply discharged batteries, which old-fashioned designs simply wouldn’t touch. And sophisticated electronic monitoring means the gassing caused by overcharging should no longer happen.

Many also have a conditioning – or float – cycle so they can be left attached for long periods with the powerpack being topped up. As well as ensuring infrequently used cars are ready to go, conditioning cycles prevent the damage that prolonged low charge levels cause.

So a battery charger is an essential for your garage, and even if you run an old motor, upgrading to the latest technology is really worthwhile. The only question is, which product should you choose?

How low can you go? Reviving powerpacks from low voltages was key here, and we tried all the chargers on a battery with less than four volts registering.

We checked speed of charge and looked for what happens in the final stages of the cycle. Our preference is for chargers that either turned themselves off or entered a conditioning stage when the battery was back to full strength. We also monitored how the conditioning cycles worked.

Trickle charging, which delivers a continuous but tiny charge, can be problematic with tired batteries, because they often gas at lower voltages than they should. Pulse conditioning charges a battery to around 95 per cent, then cuts out. Charging restarts when the level drops below 90 per cent.

We also took into account the batteries each product could tackle, lead lengths and price.

Verdict

The top three all charge sensitive modern batteries quickly and
efficiently, and feature pulse conditioning. A keen price secures the Best Buy award for Halfords’ Automatic Charger. CTEK’s Multi XS3600 is the one to go for if you have a modern Absorbed Glass Mat battery, as it has a dedicated cycle for these designs.

Meanwhile, the Black & Decker BDV1084 is more advanced than the average user would probably need, but a fast charge rate justifies its price.

Top 3

1. Halfords Fully Automatic Battery Charger
2. CTEK Multi XS 3600
3. Black & Decker BDV1084

• Email a friend
• Print this page