Battery shortages delay DIY eFoil builds across Europe

The hardest part of a home-built eFoil in Europe is no longer the board or the motor. It is finding cells you can actually trust, and finding them before the project stalls. In a FOIL.zone discussion posted April 18, 2026, a rider sizing new 12s2p packs said Nkon had a backlog on Reliance RS50 cells until June, while EVE 30P cells were backordered until May.

That detail matters because the thread was not about casual tinkering. A 12s2p or 12s3p layout means the build has moved into real pack planning, where cell choice affects safety, compatibility, weight, and whether the board ever leaves the bench. For DIY eFoil and assist builds, the supply problem now shapes the architecture as much as performance targets do. If one cell family slips by weeks, builders may have to change chemistry, adjust pack geometry, or push the entire launch date out.

Nkon’s own listings back up the delay. The Reliance INR21700-RS50 page shows a 4950mAh cell rated at 70A, marked pre-order, with an estimated shipping date of June 10, 2026. Its EVE INR18650-30P listing shows a 3000mAh cell with a 30A maximum discharge rating. Nkon’s 18650 category page also says many 18650 Li-ion batteries are directly available from stock, which is the catch in this market: stock may exist in the category, but the exact model you need can still be on backorder.

That is why builders are comparing more than one cell family. Molicel’s product pages list high-power cells such as the P45B, P60B, P60C, and M65A for demanding electric-vehicle and high-power applications. The INR-21700-P60C is rated for up to 100A maximum discharge current, while the INR-21700-M65A carries 6500mAh and sits in Molicel’s medium-power series. For builders in Europe, those numbers are not trivia. They are the difference between a pack that fits the plan and a pack that forces a redesign.

The practical warning signs are already clear: pre-order tags, long estimated shipping dates, and model-specific backlogs. In a DIY foiling scene built on custom packs and tight layouts, battery sourcing has become a trust test as much as a price check, and that is reshaping what home-built eFoils in Europe will cost, and how many will ever get finished.