Fullriver DC400-6 L16 415Ah 6V AGM Deep‑Cycle Battery

The Fullriver DC400-6 is a 6V AGM deep cycle battery rated at 415Ah at the 20-hour discharge rate, built to the Group L16/903 form factor for off-grid solar, RV, marine, and home backup applications where a sealed, maintenance-free battery bank is required. Its Absorbed Glass Mat construction immobilizes the electrolyte in a fiberglass separator rather than as a free liquid, making it non-spillable, mountable in any orientation, and approved for land, sea, and air transport under DOT 49 CFR §173.159(D). Available through A1 SolarStore as part of the Fullriver Premium Deep Cycle Series.

Key specifications

• Nominal voltage: 6V
• Capacity (C20 / C100): 415Ah @ 20-hour rate / 460Ah @ 100-hour rate; C10: 374Ah; C5: 340Ah
• Chemistry: AGM (Absorbed Glass Mat) sealed lead acid — non-spillable, valve-regulated, maintenance-free
• Group size: L16 / 903
• Reserve capacity: 885 minutes @ 25A; 229 minutes @ 75A
• CCA / CA / HPCA: 1,500A / 1,800A / 2,000A
• Internal resistance: 1.6 mΩ
• Charge voltages (6V): Bulk/Absorption: 7.35V; Float: 6.8V; TC factor: -2mV/°F/cell (-4mV/°C/cell)
• Operating temperature: 5°F to 104°F (-15°C to 40°C) recommended; -40°F to 160°F (-40°C to 71°C) maximum
• Terminal type: DTW (Dual AP and Stud); M8 stud torque: 62–80 lbs-in (5.2–6.7 ft-lbs)
• Dimensions (L × W × H w/ terminal): 11.61 × 7.05 × 16.69 in. (295 × 179 × 424 mm); weight: 123.2 lbs. (56 kg)
• Case: ABS plastic, flame-resistant rating UL94-HB; minimum bank spacing: 0.5 in. (12.5 mm)
• Certifications: UL1989, IEC60896; ISO 9001:2008 / 14001:2004 / 18001:2007; DOT/IATA/IMDG transport approved

AGM construction and non-spillable design

AGM batteries eliminate free liquid electrolyte by absorbing it into a fiberglass mat between the plates. This makes the DC400-6 non-spillable under normal and reasonably foreseeable accident conditions — allowing installation in enclosed compartments, on their sides, or in orientations that would be unsafe with flooded lead acid. The valve-regulated sealed design produces no regular outgassing and requires no water additions or specific ventilation requirements beyond those applicable to any battery installation. The ABS case with UL94-HB flame-resistant rating adds a secondary layer of safety in enclosed spaces such as RV battery bays, marine engine rooms, and indoor backup enclosures.

Capacity across discharge rates

Rated capacity varies with discharge rate — a factor that matters when sizing a DC400-6 bank against a known load. At the standard 20-hour rate the battery delivers 415Ah, but at the slower 100-hour rate (relevant for low-draw solar storage applications) it delivers 460Ah. At the 5-hour rate — closer to typical residential backup loads — capacity drops to 340Ah. Reserve capacity of 885 minutes at a 25A draw covers extended low-power loads without a recharge. For system sizing, use the discharge rate that matches your application's average current draw rather than the nameplate 20-hour figure.

Series wiring for higher system voltages

The DC400-6 is a 6V battery and must be wired in series to reach the system voltage required by most inverters and charge controllers. Two units in series produce a 12V / 415Ah bank; four in series produce 24V / 415Ah; eight in series produce 48V / 415Ah. Capacity (Ah) does not change with series wiring — only voltage increases. For higher Ah at a given voltage, series strings are wired in parallel. Bank spacing of at minimum 0.5 in. (12.5 mm) between units is required for thermal management.

Cycle life and depth of discharge

Like all lead acid chemistries, the DC400-6's cycle life is directly tied to average depth of discharge. The BCI-based cycle life chart shows a steep drop in total cycles as DOD increases above 50%. For applications where the battery bank will cycle daily — solar storage, regular backup use — keeping average DOD at or below 50% (roughly 207Ah of the 415Ah C20 rating) will significantly extend service life compared to regularly discharging to 80% or deeper. For occasional-use or infrequent discharge applications such as emergency backup, deeper discharges are more acceptable without the same cumulative impact on lifespan.

Applications

• Off-grid solar storage: Series banks of four or eight units provide 24V or 48V storage at 415Ah; charge voltages align with standard solar charge controller AGM profiles.
• RV and marine house banks: Non-spillable, sealed construction allows installation in enclosed bays and compartments; DOT/IATA/IMDG transport approval covers shipping and transport.
• Home backup: High reserve capacity (885 min @ 25A) sustains essential loads during extended outages without recharge.
• Temperature-sensitive environments: Operates within a recommended range of 5°F to 104°F (-15°C to 40°C); capacity derate applies below freezing per the temperature vs. capacity chart — temperature compensation charging (TC factor: -2mV/°F/cell) is recommended when operating outside 77°F (25°C).

Why choose the Fullriver DC400-6?

The Fullriver DC400-6 earns its place in the L16 AGM deep cycle battery category through a combination of verified capacity ratings across multiple discharge rates, dual-stud DTW terminals that accommodate heavy-gauge cabling without adapters, UL1989 and IEC60896 safety certifications, and ISO 9001/14001/18001 manufacturing standards that back the quality claim. For buyers who need a sealed, non-spillable, high-capacity 6V AGM in the Group L16 footprint for solar, RV, marine, or backup use, the DC400-6 is available through A1 SolarStore.