What EV Charger Do You Need for a 2025 Mercedes-Benz EQB 300?
A full charge takes 8.3 hours on Level 2 equipment. That speed easily covers an overnight top-up for the 205 mile battery. You need a 40 amp setup to match the car's maximum onboard charging rate.
The numbers
| Maximum AC charging rate | 9.6 kW (40 A) |
|---|---|
| Charger size to buy | 40 A |
| Circuit breaker required | 50 A |
| Outlet / connection | NEMA 14-50 outlet |
| Charge port | J1772 |
| Full charge on Level 2 | about 8.3 hours |
| Range added per hour (Level 2) | about 25 miles |
| Full charge on a 120 V outlet | about 55 hours |
| Range added per hour (120 V) | about 3.7 miles |
| EPA rated range | 205 miles |
| Energy for a full charge | about 79.3 kWh at the wall |
Why 40 amps and not more
The 79.3 kWh battery pulls a maximum of 9.6 kW from an AC power source. Feeding it a larger supply offers no benefit because the onboard hardware caps current draw at 40 amps. Buying a higher amp charger wastes money on capacity the vehicle cannot accept. Stick with the 40 amp recommendation to hit the maximum 25 miles of range per hour rate. Anything smaller increases charging time without improving efficiency.
What the install involves
Powering this setup requires a 50 amp breaker paired with heavy gauge copper wiring. Have a licensed electrician pull the wire from the main panel to your garage or parking spot. They will land the circuit on the breaker and mount a NEMA 14-50 outlet to the wall. Hardwiring is also an option if you prefer a permanent connection over a plug-in unit. Ask the electrician to check that your service panel has enough spare capacity before starting.
Chargers that match this car
Rugged metal enclosure, built for outdoor use.
Portable cordset. Works on 120 V or a 240 V outlet.
Plugs into an existing 14-50 outlet, no hardwiring.
Worth having as well
Common questions
- Can I use a standard 120 V household outlet?
- Yes, but Level 1 charging takes 55 hours to fill the battery from empty. You only recover 3.7 miles of range per hour on household current. Daily driving will quickly outpace that trickle rate.
- What plug type does the car require?
- The vehicle uses a J1772 connector. This model year falls in the industry's NACS transition. Many 2025+ vehicles ship with a NACS port but include a J1772 adapter, so a J1772 home charger still works. Confirm your car's port before buying.
- Which home chargers work with this vehicle?
- The Grizzl-E Classic 40A, Grizzl-E Mini Portable, and Home Flex NEMA 14-50 all match the 40 amp maximum rating. They plug into a NEMA 14-50 outlet and deliver the full 9.6 kW rate.
- Do I need an outdoor rated charger?
- Units like the Grizzl-E Classic feature rugged metal enclosures built specifically for outdoor use. If your parking spot is exposed to weather, choose a model designed to handle rain and temperature swings.
Other vehicles
Charging times derived from EPA data for the 2025 Mercedes-Benz EQB 300. Electrical requirements follow NEC 625.41, which sizes a circuit at 125% of a continuous load. Always have a licensed electrician verify your panel.