Tool Review: Schumacher Electric Battery Extender

Tom Karagianis, owner of Tarkus Automotive in Milwaukee, WI, is no stranger to seeing batteries going dead on his rack or in his customers’ garages. Sometimes what his customers really need is a solid battery trickle charger to keep the battery fresh.

“(This tool) works like a dream,” Karagianis says of the Schumacher SP3 Electric Battery Extender. “It’s totally idiot-proof.”

He found that the SP3 was intuitive and self-explanatory. “Yellow is charging, green is totally charged,” he notes.

Karagianis observed that the tool is so simple to use that it appeared that it could even be used by his customers.

“It’s more intended for the consumer, like guys that park motorcycles and snowmobiles for multiple seasons,” he says.

In fact, the first batteries he wanted to use it on were on his recreational equipment.

“I used battery tenders before on my snowmobiles and all it has is a red light and a green light,” Karagianis continues. “This (tool) gives more detail so you can see what’s going on. It tells you exactly what it's charging; it has an LED display that tells you exactly what percent charge a battery has.”

He also likes that the tool is set up with accessories that make it easy to connect in several different ways.

“It comes with an adapter with ring connectors so it is easier to plug in to the battery and it has a DC connector that goes into the cigarette lighter,” Karagianis notes.

There were a few questions that came up while Karagianis used the tool. For example, he knew it has a 3 amp rating, but he was not sure if he could use it to retain computer memory when changing car batteries. He also did not know if it could be used on glassmat batteries.

“Basically, it’s just a small battery maintainer,” Karagianis says. “For the money, it’s nice, it tells you if the battery is charged and automatically charges the battery."

When asked to rate the tool, Karagianis says, “It’s a 10. I like it for a battery maintainer. It basically ‘talks’ to you; it tells you the condition of the battery as soon as you hook it up.”


Product Description:

The Schumacher SP3 Battery Extender is a fully automatic microprocessor-controlled battery charger that maintains both 6V and 12V batteries, keeping them at full charge using float-mode monitoring. Perfect for charging small batteries. Great for maintaining small and large batteries kept in storage, including motorcycles, classic cars, RVs, boats. This 3 amp charger and maintainer provides a scrolling messaging display, and can automatically switch from full charge to float-mode monitoring. Other features include a quick-connect harness, the ability to snap either connector into place in seconds, reverse-hookup protection, auto-voltage detection and a hook attachment to hang the unit outside the work area for safety and convenience.