Ctek’s tips to boost battery health
Power management solutions provider Ctek has issued guidance for commercial vehicle workshops to help protect against battery-related failures.
Among the key factors impacting battery performance is cold weather, the company points out.
“At around 0°C a lead acid battery loses around 20 per cent of its capacity, at -30°C it loses around 50 per cent of its capacity (dependent on age and condition),” said Ctek training manager, Tony Zeal.
“This is due to the whole chemical reaction process within the battery slowing down leading to reduced power output.
“Because low temperature affects the chemical reaction, this means even when the vehicle is running the battery’s ability to accept charge drops, and the battery doesn’t charge as quickly.
“If a battery is in a low state of charge (as above) during extreme weather it can easily freeze, which can be very dangerous if attempting a ‘jump’ start. Because of the low state of charge, the specific gravity of the electrolyte within the battery is reduced, so it becomes more like water so freezes more easily.
“85 per cent of all battery failures are due to sulphation (caused by a low state of charge). The more active surface area you have on battery plates, the better the output; the sulphation process reduces the active plate area, leading to less power output.”
Whether a light commercial or a heavy goods vehicle, in-cab functions including heating, cooling, refrigerator and media system, as well as power for tools and equipment, tail lifts etc, are all supplied by either the starter or secondary service batteries, points out Tony.
“By regularly charging and maintaining commercial vehicle batteries, you can extend battery life by up to three times.”
Commercial vehicles making frequent drops are more susceptible to battery failure, he adds.
“Every time the vehicle is started, amperage is drawn from each battery and if the next stop is a short distance away, the alternator won’t have the time or capability to fully charge the battery. In one day, a commercial vehicle could stop and restart in excess of 30 times.
“The charge within the battery will become lower and lower, placing it at risk of sulphation or failure. It’s a myth that the alternator can bring the battery up to maximum capacity, and the short journeys often undertaken means that the alternator is working flat out all of the time, with no hope of even coming close to charging the battery.”
Workshops need to ensure that batteries are kept above 12.4V at all times, Tony says, to protect against the risk of sulphation, the biggest killer of vehicle batteries.
“This occurs when the battery charge drops below 12.4V and the electrolyte solution begins to break down, converting into lead sulphate crystals that coat the battery plates, reducing the battery’s ability to accept and hold a charge.
“One way to maintain batteries in a 24V series is to charge each 12V battery individually. The reason for this is that over time the two batteries become ‘out of balance’ with one battery at the front of the circuit absorbing all the loads placed on it; the second battery has a slightly easier life. This leads to an imbalance between the two batteries, meaning they are not performing well together.
“The individual testing of each battery to establish a clear picture of battery health and the use of two 12V chargers (like the Ctek Pro25S) will restore battery balance and bring each battery back to its full capacity.”
The company advocates introducing a battery management programme to help identify problems early, reduce battery replacements and cut failures and non-starts in cold weather. Information on the complete range of Ctek chargers and accessories for commercial vehicles can be found at the website.
