Marine Lithium Battery Manufacturer: IP67 House & Crank Packs

A battery described as "marine grade" may still be wrong for a vessel. A house bank needs reliable energy over hours, while an engine-start battery must deliver high current for a short period. Buying one pack for both jobs without checking its BMS limits, charging compatibility, and ingress protection can leave a boat without power when it matters.

## Separate house and cranking requirements

A LiFePO4 house battery is designed for repeated discharge to run electronics, refrigeration, lighting, and other onboard loads. Evaluate usable energy at the intended DoD, continuous discharge rating, cycle life, and recharge time. A higher nameplate capacity does not guarantee more usable energy if the BMS disconnects under the expected load or the battery is routinely kept near full SOC.

A crank battery is selected around engine-start current, not just amp-hours. Confirm the engine maker's cold-cranking or starting-current requirement and the battery's specified pulse duration, minimum temperature, and recovery behavior. Some LiFePO4 packs are designed for cranking; many house batteries are not. Do not assume a house pack can start an engine because its continuous current rating appears adequate.

For a combined house-and-start installation, use separate batteries or a system specifically engineered for both roles. Check the alternator, charger, inverter, and DC-to-DC charging arrangement against the battery maker's voltage limits and charging profile. Confirm that BMS charge or discharge cutoffs will not cause an unsafe voltage transient or interrupt essential vessel loads.

## What IP67 does and does not mean

IP67 indicates protection against dust ingress and temporary immersion under defined laboratory conditions. It does not mean a battery is suitable for permanent submersion, saltwater exposure at terminals, pressure washing, or installation where water can collect around connectors. Ask whether the complete enclosure, cable entries, connectors, and installed configuration were tested, and follow the manufacturer's mounting and sealing instructions.

Marine exposure adds vibration, shock, salt mist, condensation, and temperature variation. Request evidence relevant to the vessel's installation and operating environment, not only a headline ingress rating. Also verify terminal material and corrosion protection, enclosure mounting points, cable strain relief, and clearance for inspection and service.

## Compare specifications on a common basis

Consider a 12.8 V, 100 Ah house-battery shortlist. Supplier A states 100 A continuous discharge, 200 A for 10 seconds, an IP67 enclosure, and 4,000 cycles at 80% DoD under stated test conditions. Supplier B states 150 A continuous discharge, no pulse duration, IP65, and 6,000 cycles without specifying DoD or temperature. Supplier B's larger figures are not directly comparable: ask for the missing test conditions and confirm that either pack supports the vessel's peak loads.

A useful comparison table can be expressed in prose: house use, compare usable Wh at the planned DoD, continuous current, recharge limits, and cycle-life test conditions; engine start, compare peak current and duration, minimum operating temperature, and engine compatibility; installation, compare enclosure rating, dimensions, terminals, and mounting; procurement, compare certifications, warranty, MOQ, and lead time. Treat unqualified cycle-life numbers as incomplete rather than as a guaranteed service life.

## Specify the pack and verify the supplier

Provide a marine lithium battery manufacturer with the vessel voltage, house-load profile, inverter surge, engine-start requirement, charging sources, ambient temperature range, installation location, and required capacity. Include wiring diagrams and connector preferences where available. For custom packs, define cell configuration, enclosure dimensions, terminal orientation, communications, monitoring, and any parallel or series operation limits.

Ask how the BMS handles overcurrent, short circuit, cell overvoltage and undervoltage, temperature limits, and low-temperature charging. Confirm whether SOC and SOH are available through a display, CAN, or another interface, and whether alarms can be integrated with the vessel system. Request the operating manual and fault-response guidance before approving a design.

Check documentation against the exact model and intended market. UN38.3 addresses transport testing for lithium batteries; it is not a marine installation approval. IEC 62619 and UL 1973 may be relevant to industrial or stationary battery safety, but applicability depends on the product, system, and jurisdiction. Ask for current test reports or certificates, their scope, and the nameplate model they cover.

For an OEM/ODM project, agree on sample validation, production acceptance criteria, warranty terms, MOQ, and lead time before ordering. Confirm how capacity, voltage, BMS cutoffs, ingress protection, and communication functions will be checked on production units. A change in cells, enclosure, wiring, or firmware can affect performance and documentation, so require change control for approved designs.

Newbeebattery works as an OEM/ODM custom pack partner for buyers who need a specified LiFePO4 house or crank configuration. Share the vessel requirements and installation constraints early so the proposed pack, BMS, and documentation can be reviewed against the actual application.

## Conclusion

Choose the pack by duty, not by the word "marine." Match house energy and crank current separately, validate IP67 limits and BMS behavior, and compare documented test conditions, certifications, and production terms. This gives buyers a defensible specification for a dependable onboard battery system.