DEKA Duration DD300-12H 300Ah 3.6kWh 12V LiFePO4 Heated Monobloc Battery

The Deka Duration DD300-12H is a 12V 300Ah LiFePO4 Heated Monobloc Battery built on Lithium Iron Phosphate chemistry with a fully integrated Battery Management System (BMS) and built-in self-heating capability. Rated at 300Ah with 3.6kWh of usable energy, it is engineered for high-capacity applications in cold climates that demand deep, repeated cycling — including off-grid solar storage, large RV and marine house loads, golf carts, and home backup power systems — all in a sealed, IP67-rated, fire-resistant package that charges reliably down to -4°F (-20°C).

Key specifications

• Voltage / Capacity: 12V nominal / 300Ah / 3.6kWh usable energy
• Chemistry: LiFePO4 (Lithium Iron Phosphate) — maintenance-free, sealed, no venting or watering required
• Charge temperature: -4°F to 140°F (-20°C to 60°C) — enabled by built-in heating system
• Dimensions / Weight / IP Rating: 19.69 × 10.43 × 9.2 in. (500 × 265 × 232.4 mm) / 82.67 lbs. / IP67 waterproof and dustproof
• Cycle life: 6,000 cycles at 80% DoD — dramatically outlasting AGM and flooded lead-acid alternatives
• Self-discharge: Only 3% per month — suitable for seasonal storage and infrequent-use applications

Built-in heating for cold-climate charging

Standard LiFePO4 batteries cannot be safely charged below freezing — a critical limitation in cold-weather installations. The DD300-12H solves this with an integrated self-heating system that brings the cells to a safe operating temperature before and during charging, enabling full charge capability down to -4°F (-20°C). Whether installed in a northern off-grid cabin, a winter RV build, or an outdoor backup system, this battery charges reliably where standard lithium batteries would shut down or sustain cell damage. The heating duty cycle is optimized to minimize energy consumption while maintaining safe cell temperatures across a full 24-hour period.

No maintenance, no spills, far more cycles

Traditional AGM and flooded lead-acid batteries require regular maintenance, restrict usable capacity to 50–80% DoD, and wear out in a fraction of the cycles. The DD300-12H's LiFePO4 chemistry eliminates all of those limitations: the sealed, IP67-rated case prevents spills in any condition, 100% depth of discharge is fully supported, and the integrated BMS handles cell balancing automatically. With 6,000 rated cycles at 80% DoD and 99% charge/discharge efficiency, it delivers significantly more usable energy over its service life compared to any AGM alternative of equivalent size.

High-current performance for demanding loads

The DD300-12H is built for high-draw applications, with a recommended discharge current of 150A, a maximum continuous discharge of 300A, and a peak surge rating of 1,000A for 5 seconds — making it well suited for golf carts, large inverters, and other loads that demand sustained or burst current delivery. On the charging side, it accepts up to 300A maximum charge current, allowing fast recharge times when paired with a high-output charger or solar array.

Key Applications

• Cold-climate solar energy storage: Serves as the primary house battery in off-grid systems in freezing environments — 3.6kWh per unit, scalable to 16 units in parallel, and charges reliably at temperatures where standard lithium batteries cannot.
• Golf carts: High surge current, 100% usable DoD, and 6,000-cycle life make the DD300-12H a direct, long-lasting upgrade over traditional lead-acid golf cart batteries in all-season environments.
• RV and van builds: Powers lights, appliances, inverters, and electronics in motorhomes and travel trailers through all four seasons, including winter camping and cold-weather travel.
• Marine applications: Suitable for trolling motors, onboard electronics, and large house loads — the IP67 rating and sealed construction handle moisture, vibration, and tilt common in marine environments.
• Home backup and UPS: Provides dependable standby power for inverter-based home battery backup systems in cold climates requiring a high-capacity, high-cycle 12V lithium battery bank.

Intelligent BMS protection and safe chemistry

• Full BMS protection: Guards against overcharge, over-discharge, short circuit (1200A / 500µs), and high-temperature cutoff (149°F / 65°C) — automatically reconnecting once safe conditions are restored.
• Fire-rated ABS PC casing: The enclosure is built from fire-rated materials and rated IP67, making it one of the safest and most durable housings available in a monobloc lithium battery.

Flexible system configurations

The DD300-12H supports up to 16 units in parallel or configurations of 4-parallel by 4-series, allowing scalable energy storage systems from a single 3.6kWh unit up to larger 24V or 48V battery banks. Threaded M8 insert terminals ensure secure, vibration-resistant connections throughout.

Charging and system compatibility

The DD300-12H is compatible with any LiFePO4-profile charger or solar charge controller. Absorption voltage should be set to 14.2–14.6V; float voltage to 13.6–13.8V; recommended charge current is 150A with a maximum of 300A. It is compatible with any PWM or MPPT solar charge controller configured to a lithium or LiFePO4 charge profile.

Why choose the Deka Duration DD300-12H?

The DD300-12H is the cold-weather solution for buyers who need all the advantages of a high-capacity LiFePO4 battery — 3.6kWh, 6,000 cycles, 300A continuous discharge, and IP67 construction — without sacrificing cold-temperature charging capability. It is the direct upgrade for any large-capacity installation where a standard lithium battery's freeze-charging limitation is a dealbreaker. Certified to UN38.3, UL 1973, IEC62619, UL9540A, UL1642, and CE standards.

Dimensions

19.69 × 10.43 × 9.2 in (500 × 265 × 232.4 mm)

Weight

82.67 lbs (37.5 kg)