Auto Service World
Feature   November 1, 2014   by Andrew Brooks

Power Profile

Temperature extremes are a significant threat to battery performance

t’s always a good idea to ensure that a vehicle’s battery is in top operating condition. With the approach of another Canadian winter, many drivers will be especially aware of the need for a secure power source – but, in fact, extreme heat is the greatest threat to automotive batteries.

“Heat speeds up all chemical reactions,” says Bob Osinski, director of retail sales for Exide Technologies. “Because a car battery works by using a chemical reaction, motorists with older batteries might get stranded by premature failure during a relentless heat wave. High outside temperatures, combined with stop-and-go traffic on overheated pavements, can drive the under-hood temperatures to more than 200°F [93°C].” When you consider added heavy electrical loads such as air conditioners, power windows and stereo systems, Osinski says, hot summer conditions can be deadly for a car battery.

However, either temperature extreme poses a challenge. Drivers should make sure the battery is fully charged. They should also be reminded of the importance of keeping the engine well maintained year-round. Basic steps for battery health include getting regular tune-ups, changing the oil and keeping the radiator fluid topped up, watching for battery terminal corrosion and making sure all connections are clean and tight. Service centres should emphasize the importance of having the battery tested. If the car is difficult to start, check the electrical system; if any component is in marginal condition, it’s probably time to replace it, Osinski adds. Cracks or holes in the battery container, the cover or the vents are major warning signs.

Service centres can help motorists avoid trouble in cold weather by reminding them to drive the car long enough to recharge the battery, while trying to avoid frequent stops and starts over a short period of time, Osinski says. “To efficiently recharge a battery while driving, motorists should minimize electrical loads, such as windshield and rear window defrosters, radio, extra lights and electric windows.”

One of the most important developments in battery technology is the advent of new battery charger products. These eliminate much of the worry over battery conditions at any time of year, but especially during cold weather. “If the battery is connected to a quality maintainer product, like an OPTIMA Digital 1200 or Digital 400, nothing else needs to be done,” says Scott Parkhurst, OPTIMA Batteries media relations. “It can be disconnected or removed from the vehicle, but this is not necessary unless the vehicle’s storage location will be exposed to freezing temperatures for extended periods.” While it happens rarely, automotive batteries can freeze, doing severe and permanent damage.

The traditional battery charging process is fraught with guesswork. “Without properly testing the battery before beginning a charging regimen, recharging levels and times are guesses,” Parkhurst says. “The hope for most technicians is that the battery will acquire enough of a charge to be maintained by the alternator/regulator in the vehicle. If there are issues with the vehicle’s voltage regulator, overcharging can still occur, of course, and the alternator should only be maintaining the battery anyway.”

The newer chargers remove much of this guesswork. That guesswork was one reason OPTIMA chose to engineer all-new battery charging products with their Digital 1200 and Digital 400, employing computer-controlled charging algorithms. Evaluating the condition of the battery, and then giving it the proper level of charge for the ideal time to maximize its capacity is a very complex procedure, and computerization makes the task a lot easier.

“It’s best to use a charger to bring it up between 12.5-13.0 volts, and then let the alternator maintain it from there. If the battery is incapable of holding a charge at that level, it requires replacement,” Parkhurst says. “Chargers are simply the safest and best possible way to test and charge 12-volt batteries of all kinds – flooded and AGM, SLI and Deep Cycle. Other concerns facing technicians – like the dangers of spark creation and potential hydrogen combustion as a result – are also minimized by the no-spark technology engineered into every OPTIMA Digital Charger.”

An added benefit of the newer charger technology is the availability of printouts showing the state of the battery. “If technicians are able to explain what the various information on the printout is reporting to the consumer, it can justify sales,” Parkhurst says. “Naturally, consumers aren’t anxious to spend money to replace a component that’s still functioning, so the printout provides legitimate evidence of impending failure.” However, many shops that can produce printouts don’t use them, while many others can’t produce printouts at all since the capability still isn’t generally offered as a standard product feature.

Hot and cold

One significant cold-weather threat is degradation of cranking capacity. “Battery Council International statistics indicate that when the outside temperature is 80°F [27°C], a fully-charged battery has 100 per cent of its power available to start the car,” says Exide’s Osinski. “When the temperature drops to 32°F [0°C], a fully-charged battery only has approximately two-thirds of its power available. And at 0°F [-18°C], that same fully-charged battery has only 40 per cent of its power available to start the vehicle. This clearly emphasizes the need for motorists to keep their battery fully charged.”

While heat causes deterioration of the battery’s plate through corrosion from the inside out, extreme cold attacks and strains the battery’s cold cranking availability, says Gale Kimbrough, manager of engineering and technical services, Interstate Batteries Inc. Kimbrough says the second leading cause of automotive starting battery failures is plate paste sulfation from inactivity or short drive times.

Kimbrough also advises caution when using battery chargers. “Don’t connect a charger across the battery in a vehicle unless you are sure the charger’s voltage regulation stays below 16.0 volts,” he says. “A battery charger which has a high voltage regulation level – above 16.0 volts – may damage some components of a vehicle’s sensitive electronic control system. Older chargers are often inefficient because they don’t incorporate solid state technology which better controls the voltage spikes and currents to the battery.”

Kimbrough says drivers and technicians should never rely on the alternator to finish recharging a battery. “Alternators should be considered a maintainer, not a battery charger. The alternator is there to primarily provide power for the vehicle’s accessories. Its secondary job is to provide power for the battery. The alternator’s voltage regulation is set for the vehicle’s accessories and is not high enough for medium or deep discharge levels.”

OPTIMA’s Parkhurst points out that using an alternator to recharge a deeply-discharged battery – something that happens in any common jump-start scenario – places a tremendous strain on the alternator and shortens its lifespan, which is a far more expensive repair than replacing a car battery. “In fact,” he adds, “many alternator manufacturers post warnings on their boxes telling consumers not to use alternators to recharge dead batteries.”

Vehicle industry innovations and batteries go hand-in-hand, Kimbrough says. “Recent vehicle modernizations like start-stop technology require a battery that can deliver three to five times the number of starts of an ordinary vehicle while providing deeper cycling characteristics. EFB [Enhanced Flooded Batteries] and AGM batteries will be required to properly power these vehicles. Most flooded and even AGM batteries produce thousands of cranks but can only produce 20 to 25 deep cycles – leaving a light on and discharging the battery to a no-start condition. We now have AGM pure lead batteries that not only produce high cold cranking amps but also hundreds of deep cycles.”

Print this page


Have your say:

Your email address will not be published. Required fields are marked *