12 amp charger for CX & SX: Bosch launches fast charger for e-bike batteries - finally!

Just in time for the Bike Festival in Riva del Garda, Bosch has unveiled its e-bike innovations for summer 2026. In addition to the Performance Upgrade 2.0, which provides the CX and CX-R with more torque and support, the quick charger is certainly the real highlight for many e-bikers.

While Bosch had a Fast Charger with 6 amps in its programme for older battery generations early on, the current Smart System drives only had the classic, slow charger with 4 amps.

Bosch 12A Charger: Fast charging thanks to GaN technology

The new 12A charger is said to charge up to three times faster than the previous Bosch charger. Bosch claims a charging capacity of 500 watts. A Powertube 800 should thus recover 50 per cent capacity in around one hour of charging. These are pretty much exactly the values we achieved with the Fast charger of the Avinox system in our tests have determined.

This is made possible by so-called GaN technology (gallium nitride). This modern semiconductor technology generates significantly less waste heat than conventional semiconductors, which enables more efficient heat management.

Despite its high performance, the charger remains compact and backpack-compatible at less than one kilogramme. By comparison, the Avinox quick charger weighs 1100 grams.

Specialized also has a quick charger for its new 3.1 motor in the Levo 4. This should charge even faster. Unfortunately, at 2.5 kilos and with expansive dimensions, it is too big and too heavy for the rucksack.

According to Bosch, faster charging is not expected to have a negative impact on the service life of the battery. Whether the new charger will also allow smart functions such as a particularly gentle charging process or limiting the charge level via the app remains to be seen. According to Bosch, this is still under development until the sales launch at the end of 2026.

Why fast charging?

There are various ways to extend the range of an e-bike. Second battery, range extender or recharging on the go. The latter option can be particularly interesting, as a fast charger is usually lighter and smaller than a second battery and also cheaper. If the charging process runs quickly, considerable profits are also possible. This can be really helpful, especially for bikes with a permanently installed battery.

4 A & 12 A - charging times in comparison

Our comparative measurements with the classic 4A charger from Bosch compared to the 12A charger from Avinox show why a fast charger makes sense. If you believe the manufacturer's claims, the 12A charger from Bosch should be just as fast as its Avinox counterpart, but a little lighter.

Charging times 800 Wh battery

Avinox 12 A, 1100 grams:

• from 0 to 100 %: 2:33 hours
• 1 hour charging: 48 %

Bosch 4A, 700 grams:

• from 0 to 100 %: 6:08 hours
• 1 hour charging: 25 %

We will provide the figures for the new Bosch Fast Charger as soon as we get our hands on a production-ready product for testing. The 12A charger is compatible with all Bosch batteries in the "smart system" and should be available from the end of 2026. A price has not yet been communicated.

Opinion of the BIKE editorial team

This step was long overdue! We were already hoping for a faster charger for Bosch e-bikes when the Smartsystem was introduced four years ago. In vain. With the success of the DJI Avinox - including a consistent 12A fast charger - the Swabians' omission became obvious. While the new charger is dispensable for some, it can be a real game changer for others. At last.