AutoMeter Battery Extender
by Hib Halverson
If your V is not a daily driver, it may spend long periods parked or stored. If that’s the case, it’s possible you’ve had a dead battery. Even the best battery, when not connected to anything, slowly discharges because of the chemical processes at work inside it. Once hooked to your car’s electrical system and when the alternator is not charging, besides that tiny, self-discharge rate, a battery has a small, constant load on it from things like: the memories in the car’s various computers, clock, anti-theft devices and, if you open the doors while the car sits, interior lighting.
If a period of non-operation is several weeks, it is possible the battery may discharge to the point of a no-start condition. Then, you either charge the battery or jump-start the car. These full-discharge-then-recharge or “deep cycles” reduce battery life. The durability of typical automotive batteries is significantly reduced if they’re subjected to deep cycles on a regular basis. Even premium batteries, such as the Odyssey Extreme and Performance series batteries, which are more tolerant of deep cycles, cannot be subjected to frequent, regular deep discharge/recharge cycles with out eventually having their performance degrade.
When the V-Net debuted it’s Product Evaluation Pages, one of the first products we tested was the first-generation AutoMeter Battery Extender. This device was one of the early entries into “smart” battery charger business, which today is huge with a plethora of products from various manufacturers. The original Battery Extender (PN 9201) proved to be quite a successful product selling about 50,000 units in 20 years on the market. We should add that two decades is an amazing life span for a product like a battery charger.
A “smart” charger, is designed to keep vehicle batteries charged during periods of non-operation lasting longer than a couple of weeks. Typically, they have two charge rates: a maximum rate of between 1.5 and 5-amps and a maintenance rate of between 200-miliamps and 1.0-amps.
When a “smart charger” is connected, if it senses a battery which is not fully charged, it switches to it’s maximum charge mode. As battery voltage reaches an optimal level, the charger switches to its maintenance mode which
Upon connection, if the battery is partially discharged, a smart charger, such as the Battery Extender BEX-5000 we tested for this article, brings a battery up to full charge using a three-amp rate. At that point, a microprocessor senses battery voltage at a nominal level and backs-off the charge rate to between 0 and 250 milliamps, depending on load. It “floats” the charge current at that level which is just enough to keep the battery at its optimal charge voltage, which depending on battery type, is 12.6-12.8-volts. This feedback-controlled, reduced-charge rate eliminates overcharging and extends battery life. There is no need to monitor an AutoMeter Battery Extender. Just plug it in, connect it to the car and forget it.
In 2015, AutoMeter redesigned the Battery Extender product line incorporating more modern technology, a widened feature list and more competitive pricing. This second design AutoMeter charger line, known as “BEX” was released in three versions, 1.5-Amp, 3.0-Amp and 5.0-Amp. Of those three, the 5-Amp, BEX-5000 sold out in a matter of weeks, so we had to wait a number of months for AutoMeter to restock and provide a unit for testing.
One advantage of the BEX-5000 over the older Model 9201 Battery Extender is that the new unit has three modes of operation: charging, maintenance and desulfation. The first two modes are pretty much standard faire for any smart charger and were available from the old 9201s. What’s new is the desulfation mode. Lead-acid storage batteries can have a problem called “sulfation” where lead-sulfate crystals develop on the plates. When a battery becomes “sulfated” it’s ability to hold a charge is degraded. Mild cases of sulfation can be mitigated by “pulsing” the charge voltage and current which can “knock” the sulfation off the plates. If the BEX-5000 senses sulfation is developing, it goes into the “de-sulfation” mode where voltage and current are varied in a way that causes the lead-sulfate crystals to separate from the plates.
Another improvement of the new Battery Extender design is that the unit’s housing is made of a lightweight plastic and is sealed making the device water-resistant to the IP65 standard which means that, not only can it stay dry during a three-minute spray with a water jet but it’s also is completely impervious to dust. In our testing we found the new, sealed housing not as valuable as an anti-moisture-and-moisture measure as it is an “anti-critter” measure. We have several of the old Battery Extenders in service and one of them is used outdoors. We’ve found that insects, especially little spiders, like the interior of the first design Battery Extenders–so much so that two or three times a year, we have to unplug it, then use shop air to blow though the housing’s exterior vents to get rid of dead insects and spiders (live or dead). In short, we definitely like the hard plastic housing used by AutoMeter in the new Battery Extender design.
Three features we like in the BEX-5000 are it’s automatic overcharge protection, reverse polarity protection and spark-free connection. With the first two systems, there’s very little chance of screwing up a battery by not paying attention to how long it’s connected nor connecting red to black and black to red. With the third, you don’t have to worry about a little spark when you connect the second cable and we’ll remind you now to always connect the positive cable (red) first and the negative cable (black) last.
The final advantage–and it’s a big one–of the new BEX line is that they are priced lower and. in the cases of the BEX-1500 and BEX-3000. a lot lower than the original products were priced. We can thank a modern circuit design, lower component costs and lower-cost manufacturing for that.
Battery Extenders are compatible with all types of lead-acid batteries: wet cell or “flooded”, absorbent glass mat or “AGM” and gel cell batteries. Battery Extenders always come in a kit which includes two sets of leads. One set has traditional spring-clips on one end and another set with ring terminals on one end. Both sets of leads connect to the charger with a quick-disconnect mechanism. The BEX-5000’s safe ambient temperature range is -4°F to 122°F. Outside of that range, the device may malfunction or just fail to function. All of the BEX series chargers use the normal AC current available in North America. The actual voltage range the charger will tolerate is 108-volts AC to 132-VAC. The BEX-1500 and BEX-3000 have a 12-volt output. The BEX-5000 has 6-,8-, 12- and 16-volt outputs which are selected with a button on the device. When operating with at the first three voltages, the maximum charge current available from a BEX-5000 is 5-amps. When the 5000 is run in the 16-volt mode, max. current is 3-amps.
For more information on AutoMeter’s BEX line of smart battery chargers, see the battery charger section of AutoMeter’s web site. http://www.autometer.com/test-equipment/chargers.html#1&profile=products