Description
The US AGM 8D is the biggest-capacity 12V battery in U.S. Battery's AGM range: 308Ah at the 20-hour rate and 252Ah at the 5-hour rate. If your priority is the longest runtime from a single 12V case, this is where the lineup tops out, and the price you pay is weight, a hefty 169 pounds.
Discharge figures show how it holds up under load: 180 minutes at 75 amps, 262 at 56 amps and 728 at 25 amps. Its 10.6-inch width makes it the broadest of the 12V AGMs here, and at 8.86 inches tall it is low enough to slide under shelving that a taller battery would hit. Compared with the US AGM 4D, you get 62Ah more at the 20-hour rate in exchange for roughly 26 more pounds and 1.15 inches of width.
Think about handling before you order. One person cannot lift this battery, so plan on a hoist or a two-person move, and confirm your tray can take the 20.5 by 10.6 inch footprint. The case is heat-sealed ABS, and the AGM design lets you run it on its side.
Specifications
| Model | US AGM 8D |
| Voltage | 12V |
| Capacity @ 20hr | 308Ah |
| Capacity @ 5hr | 252Ah |
| Minutes of Discharge @ 75A | 180 |
| Minutes of Discharge @ 56A | 262 |
| Minutes of Discharge @ 25A | 728 |
| Length | 20.5in (521mm) |
| Width | 10.6in (268mm) |
| Height | 8.86in (225mm) |
| Weight | 169 lbs (77kg) |
| Case Material | ABS, heat sealed |