A wireless battery can be charged in or out of the tool simply by placing it on the charger (this drill has a European model number).
Bosch Tools A wireless battery can be charged in or out of the tool simply by placing it on the charger (this drill has a European model number).
Electrical current is fed into a coil in the charger, where it is converted to electromagnetic waves that are “transmitted” to the battery pack. The electromagnetic waves are received by a coil in the pack and converted to the current used to charge battery cells.
Electrical current is fed into a coil in the charger, where it is converted to electromagnetic waves that are “transmitted” to the battery pack. The electromagnetic waves are received by a coil in the pack and converted to the current used to charge battery cells.
The charger can be placed in an optional frame that the battery slips into. It can be used with a tool and battery or battery alone.
The charger can be placed in an optional frame that the battery slips into. It can be used with a tool and battery or battery alone.
An optional holster accepts charger and driving tools, and will hold them in position so charging can take place in a moving vehicle or elsewhere.
Bosch Tools An optional holster accepts charger and driving tools, and will hold them in position so charging can take place in a moving vehicle or elsewhere.

The Bosch wireless charging system we covered in June has been released for sale in the U.S. The system consists of a wireless (inductive) charger and specially equipped Li-Ion batteries that fit the company’s 18-volt tools.

Inductive charging has been around for years and is used to charge small devices such as cell phones, electric razors, and electric toothbrushes without removing the battery or making physical electrical contact. Wireless systems rely on a pair of coils; the one in the charger functions as a transmitter and the one in the battery as a receiver. Place a device on top of a compatible charger and energy is sent to the battery in the form of electromagnetic waves.

I first wrote about this system when it was newly released in Germany and at the time there were many unknowns, such as charging time, the nuts and bolts of operation, and what it would cost if and when it came to the U.S. We know those things now.

Bosch’s new batteries can be charged by plopping the tool on the charger. Do this whenever you put the tool down and the battery will undergo charging whenever the tool is not being used. All that’s required is that the tool be able to stand upright on the charger. If that’s not possible the battery can be removed from the tool and charged by itself on the wireless charger or charged in the traditional manner with the chargers that work with standard Bosch batteries.

The company is initially offering a 2.0 Ah SlimPack (WCBAT612) but there appears to be a second model in the works because the manual mentions another pack (WCBAT625). It’s probably some kind of FatPack.

Charging Time
According to the manual, the pack can be charged to 80% of its capacity in 30 minutes and 100% capacity in 50 minutes. By way of comparison, the company’s existing standard charger (BC660) requires 65 minutes to charge a 2.0 Ah pack.

These charge times are in line with those of the average battery system (though slower than Makita’s, which claims a 20-minute charge time for 2.0 Ah packs). The charging speed of the wireless system may only be average, but given the pack will likely be charged intermittently throughout the day, speed may not matter.

Nuts and Bolts of Charging
The battery should sit flat on the charger with no stray pieces of metal (washers, filings, etc.) between them. The charger is equipped with "foreign object detection" which prevents it from operating when metal objects that don't belong are present because the electromagnetic field could make them hot enough to start a fire. There are the usual diagnostic indicator lights on the front of the charger, which do something cool; they function as a battery gauge, so you can tell at a glance the level of charge. There is also a gauge on the battery.

The charger can be used by itself or with various accessories. A frame, which can be fastened to a bench or wall, can be used to hold the tool and battery against the charger. A holster accessory can be used to hold the tool (drills and drivers only) on the charger in a moving vehicle, without fear it will fly out when you hit the brakes.

Pricing
The wireless charger and batteries can be purchased separately or with select Bosch tools. Online pricing for a 2.0 Ah wireless SlimPack is currently $89, about $20 more than a standard SlimPack. The wireless charger can be found for $59, the charger frame for $12, and a charger with holster (not currently offered separately) for $109. All four items (wireless SlimPack, charger, frame, and holster) can be purchased together for $199. It’s a brand new system and currently sells for the MSRP, though prices may come down after it has been out for a while.

Is Wireless Charging Worth It?
Wireless charging doesn’t make sense for everyone. It’s best suited to the person who does bench work and can plop the tool on the charger when he’s not actually using it. Cabinet making and assembly work are two things that come to mind. When I was a finish carpenter I usually set up a work table, and a charger was one of the things on it; a wireless charging system would have been just the thing for that setup.

The 2.0 Ah wireless batteries currently available are not a good choice for power-hungry tools like recip saws, circular saws, and large rotary hammers. Higher capacity wireless batteries may be on the way, but won’t make much difference to those who use recip saws and circular saws—which won’t sit flat on a charger and are rarely used within easy reach of one. You could charge the batteries wirelessly, but you’d have to take them out of the tool—at which point you might as well use a regular charger.

The shortcomings of wireless tool battery charging may diminish in time. It’s an entirely new system and as with anything involving tech, the first generation of something is never as good as the second, fifth, or tenth.