Press release — content provided by ATMOCE · 2026-08-30 · ESS News
Frankfurt, August 25, 2026 — ATMOCE has launched the MS-8K-U PRO, a residential energy storage system that extends warranty coverage to 25 years and pairs an 8 kWh capacity with 5 kW of output, completing what the company calls the industry’s first 25-year residential solar and storage system alongside its MI-Series microinverters.
The MS-8K-U PRO’s headline specification is its warranty term. The system’s LFP (lithium iron phosphate) battery is rated for up to 15,000 cycles, and ATMOCE pairs that durability with a 25-year warranty across the core system components. The standard MS-8K-U model carries a 10,000-cycle rating, positioning the PRO variant for households that plan to hold a solar-plus-storage asset over the full life of the installation.
The battery delivers up to 8 kWh of rated energy at a nominal DC voltage of 25.6 V, with a claimed 51 MWh of lifetime energy throughput. DC round-trip efficiency is 96%, while the full AC round-trip efficiency is 90%.
The MS-8K-U PRO operates below 30 Vdc, an “extra-low voltage” architecture that avoids the high-voltage DC bus common in residential battery systems. ATMOCE pairs this with its Trinity Safety design — layered electrical, thermal and system protection — and a fire suppression system. The enclosure is IP66-rated for outdoor installation, with an operating temperature range of −30 to 55 °C and intelligent air cooling.
On the power electronics side, the system uses ATMOCE’s proprietary Cyclo-NovaFlux topology for direct low-voltage DC-to-AC conversion, which the company says reduces conversion stages and system complexity. A semiconductor-based PCS and a DAB-based AC architecture round out the design.
The MS-8K-U PRO is AC-coupled, so it can be added to existing solar installations that use third-party PV systems and inverters with minimal changes to the original design. It supports single-phase, three-phase and split-phase configurations, and is compatible with the ATMOCE Gateway for self-consumption, time-of-use and grid ancillary services.
Software features include dynamic tariff optimisation and a VPP-ready architecture, with monitoring through ATMOCE Cloud and the ATMOZEN app for real-time monitoring, predictive diagnostics and intelligent energy management.
| Parameter | MS-8K-U PRO |
|---|---|
| Rated battery energy | 8 kWh |
| Nominal battery capacity | 314 Ah |
| Nominal DC voltage | 25.6 V (max 28.8 V) |
| Chemistry | Lithium iron phosphate (LFP) |
| Cycle life | 15,000 cycles (PRO) / 10,000 (standard) |
| Max. output power | 5 kVA (continuous 4.5 kVA) |
| AC round-trip efficiency | 90% |
| DC round-trip efficiency | 96% |
| Dimensions (H×W×D) | 830 × 480 × 195 mm |
| Weight | 76.5 kg |
| Mounting | Floor or wall mount |
| Ingress rating | IP66 |
| Operating temperature | −30 to 55 °C |
| Noise | < 35 dB |
| Compliance | IEC 62619, ISO 13849, IEC 62477-1, VDE-AR-E 2510-50 |
“Ultimate LCOE is about creating value over the full period of ownership,” said Giorgio Chen, Founder, Chairman and CEO of ATMOCE. “A 25-year warranty is not simply a longer commitment. It must be supported by technologies designed for durability, efficiency and reliable performance over decades.”
ATMOCE’s positioning centres on a mismatch the company sees in residential solar: PV modules are commonly warranted for 25 years or more, while other core components historically carry shorter coverage. By extending 25-year coverage to the battery and power electronics, the MS-8K-U PRO aims to reduce replacement uncertainty and let homeowners treat solar and storage as one integrated, long-term energy system rather than components with different replacement cycles.
ATMOCE — MS-8K-U / MS-8K-U PRO Data Sheet (English)
ATMOCE — 8KPRO Deep Dive, 25 August 2026 (product brief)
