21.6V 4.5Ah IP68 Underwater Scooter Battery Pack — Depth-Rated to 60 Meters | OEM Supply

Q1: Why is EPDM specified for the O-ring material rather than standard silicone, and does it hold up under repeated pressure cycling in dive operations?

Standard silicone O-ring compounds perform adequately in static or infrequent immersion scenarios but show measurable compression-set degradation when subjected to the repeated pressure cycling that characterizes active diving use — multiple descents and ascents per session, across hundreds of dive cycles over the product service life. Each pressure cycle compresses and releases the O-ring, and compounds with lower elastic recovery gradually lose the force needed to maintain a watertight seal. EPDM’s cross-linked polymer structure provides significantly higher elastic recovery after compression cycling, maintaining consistent seal force across the service life of the pack. Additionally, EPDM’s saturated backbone resists oxidative attack from chlorine and ozone — relevant for both pool use and open-water environments where ozone levels in surface water vary seasonally. The secondary epoxy potting layer on internal compartments provides a non-elastomeric barrier that is unaffected by any of these chemical exposures.

Q2: The LEFEET S1 Pro has a specific battery bay geometry and connector interface. How is dimensional consistency maintained across production batches?

The LEFEET S1 and S1 Pro battery bay dimensions are held as fixed parameters in our enclosure machining program, with first-article inspection performed at the start of each production run using calibrated go/no-go gauging on the critical fit dimensions — housing length, width, height, and O-ring groove depth and width. Any dimensional reading outside tolerance triggers a tooling offset correction before production continues. The connector pin assignment and housing interface geometry for both LEFEET platforms are documented in our production records. For integration into a modified LEFEET chassis or a third-party device with similar geometry, provide the battery bay drawing and connector spec before prototype ordering so we can confirm fit against your specific tolerance stack before committing production.

Q3: What is the minimum order quantity, and what parameters can be adjusted for OEM programs?

Prototype validation orders using existing enclosure tooling can proceed at 10 to 20 units. Full OEM customization is available across all primary parameters: voltage, capacity, declared waterproof depth and duration, enclosure outer dimensions, connector type and pin assignment, and BMS communication protocol. Cell brand specification — including Samsung SDI retention or alternative cell sourcing for volume cost optimization — can be discussed for established production programs. Projects requiring new enclosure tooling involve a tooling cost and lead time discussion at the proposal stage. Submit your application specification and we return a technical proposal with pricing and lead time within 48 hours.

Q4: How does the underwater hot-swap function work on a DPV, and what connector interface is required?

Underwater hot-swap allows the battery to be disconnected and replaced while the scooter remains submerged — eliminating the need to surface between battery changes during extended dive operations or multi-diver programs where multiple units cycle through the same device. The function requires a wet-mate connector: a connector type specifically rated for make-and-break operations while both halves are submerged, with sealed pin and socket housings that exclude water from the electrical contact area during the connect and disconnect sequence. The default connector on this pack supports wet-mate operation. If your platform uses a different wet-mate connector standard — SubConn, Cobalt, or a proprietary interface — specify the connector type and pin assignment at inquiry stage and we configure the pack to match.

Q5: What does the IP68 test documentation package contain, and how does it support CE marking submissions for DPV products?

The documentation package shipped with every OEM order contains four elements: the air-pressure leak test record for each production batch (test pressure value, hold duration, pass/fail threshold), the water immersion test record (declared depth, soak duration, water temperature, pass/fail result), photographic documentation of the immersion test procedure, and the UN38.3 transport compliance certificate. For CE marking of a DPV product under the applicable Machinery Directive or Low Voltage Directive, the IP68 test records for the battery component serve as technical evidence in your product technical file, demonstrating that the battery has been tested to a declared waterproof standard appropriate to the product’s operating environment — a documentation requirement that notified bodies frequently request for aquatic equipment applications.

Q6: What is the storage recommendation for this pack between dive seasons, and how does storage in a sealed enclosure affect long-term cell health?

For storage periods exceeding 30 days, maintain the pack at 40–60% state of charge — approximately 22.2V to 23.4V on the pack terminals. Storing at full charge accelerates electrolyte oxidation at the cathode interface, reducing available capacity over repeated storage cycles; storing at full discharge risks copper dissolution at the anode if the pack voltage drops below the BMS undervoltage protection threshold during self-discharge over an extended storage period. The sealed IP68 enclosure does not introduce additional storage risk compared to a vented pack at the same state of charge — there is no trapped gas effect at normal storage temperatures. Storage temperature should not exceed 35°C. For packs stored longer than 6 months, a single charge-discharge cycle to verify capacity before returning to active use is recommended practice.