NOCO GENIUS2 battery charger
The GENIUS2 charges at 2 amps and NOCO rates it to recharge batteries up to 40 Ah and to maintain any size. It is twice as fast as the GENIUS1 on the same battery.
Checked against sources on by the TrueAmps editorial team.
- Charge current
- 2 A
- Battery voltages
- 6 V / 12 V
- Recharges batteries up to
- 40 Ah
- Lithium (LiFePO4) mode
- Yes
- Weight
- 1.1 lb
- Safety listing
- UL 1236
Ratings are the manufacturer's own, from NOCO's spec page, checked September 24, 2026. Safety listing: ETL (Intertek), directory record, checked September 24, 2026.
See NOCO GENIUS2 on Amazon (paid link)
Battery size it is rated to recharge
What 2 amps changes
Doubling the current halves the time. By NOCO's charge-time ratio a 30 Ah battery at half charge takes about 11 hours instead of 22.5 on the GENIUS1.
It is still a small charger for car batteries. For a flat car battery the GENIUS5 or GENIUS10 is the tool; the GENIUS2 is for keeping one topped up, and for recharging small batteries in a reasonable time.
NOCO lists an IP65 housing and includes a mounting bracket, so it can live permanently in a garage or on a trailer.
How long the GENIUS2 takes
Estimated hours from half charged to full, using the charge-time ratio in NOCO's own manuals. How the estimate works.
| Battery | From 50% | From flat |
|---|---|---|
| 10 Ah | 3.8 h | 7.5 h |
| 20 Ah | 7.5 h | 15 h |
| 35 Ah | 13 h | 26 h |
Nearest chargers in the range
| Model | Amps | Up to Ah | Lithium |
|---|---|---|---|
| NOCO GENIUS2 | 2 | 40 | Yes |
| Battery Tender Junior Multi-Chemistry | 1 | - | Yes |
| NOCO GENIUS2D | 2 | 40 | No |
All battery chargers side by side
Head to head: GENIUS1 vs GENIUS2
GENIUS2: questions people ask
GENIUS1 or GENIUS2 for a motorcycle?
Both handle motorcycle batteries. The GENIUS2 recharges twice as fast and is rated up to 40 Ah against 30 Ah for the GENIUS1.
Check the GENIUS2 listing on Amazon (paid link)