NOCO GENIUS5 battery charger
The GENIUS5 charges at 5 amps and NOCO rates it to recharge batteries up to 120 Ah. By NOCO's own manual, a 40 Ah battery at half charge is full in about 6 hours.
Checked against sources on by the TrueAmps editorial team.
- Charge current
- 5 A
- Battery voltages
- 6 V / 12 V
- Recharges batteries up to
- 120 Ah
- Lithium (LiFePO4) mode
- Yes
- Weight
- 1.5 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 GENIUS5 on Amazon (paid link)
Battery size it is rated to recharge
The size most car owners need
Five amps is where a car battery charger stops being an overnight-and-then-some job. NOCO's manual lists 6 hours for 40 Ah, 12 hours for 80 Ah and 15 hours for 100 Ah, all from 50 percent charge.
Check the Ah number on your battery label against that 120 Ah ceiling. It charges 6 V and 12 V lead-acid and lithium LiFePO4, per NOCO's spec page.
How long the GENIUS5 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 | 1.5 h | 3.0 h |
| 20 Ah | 3.0 h | 6.0 h |
| 35 Ah | 5.3 h | 11 h |
| 50 Ah | 7.5 h | 15 h |
| 70 Ah | 11 h | 21 h |
| 100 Ah | 15 h | 30 h |
Nearest chargers in the range
| Model | Amps | Up to Ah | Lithium |
|---|---|---|---|
| NOCO GENIUS5 | 5 | 120 | Yes |
| NOCO GENIUS2D | 2 | 40 | No |
| NOCO GENIUS10 | 10 | 230 | Yes |
All battery chargers side by side
Head to head: GENIUS5 vs GENIUS10
GENIUS5: questions people ask
How long does the NOCO GENIUS5 take to charge a car battery?
NOCO's manual gives 6 hours for a 40 Ah battery and 12 hours for 80 Ah, from 50 percent charge. A fully flat battery takes roughly twice as long.
Can the GENIUS5 charge a lithium battery?
Yes. NOCO lists lithium (LiFePO4) among its supported chemistries.
Check the GENIUS5 listing on Amazon (paid link)