
40FT Container Energy
Storage System
A 7.5MWh-class liquid-cooled 40-foot container for utility-scale plants — 18 clusters of 314Ah LiFePO4, multi-level BMS, integrated chiller, fire protection and electrical bay, all pre-integrated and factory-tested. Fewer containers per megawatt-hour means lower BOS cost, faster builds and simpler O&M.
Why Liquid Cooling Wins at Scale
Eighteen 314Ah clusters under precise liquid cooling — higher density, tighter temperature consistency, longer battery life.
Liquid-Cooled Thermal Management
Closed-loop liquid cooling keeps every 314Ah cell within a ±3°C temperature window — more stable operation, lower auxiliary consumption and longer cycle life.
Standardized & Expandable
Standardized 40FT design, easy to expand and maintain — parallel multiple 7.5MWh containers into utility-scale plants of any size.
Multi-Level Fire Protection
Built-in fire extinguishing, temperature control and early warning systems with a fault classification and protection mechanism.
Integrated Monitoring
Integrated monitoring system with LCD, RS485/CAN battery communication and RS485/TCP-IP EMS uplink for remote O&M.
Independent Air Duct Design
Independent air-duct layout isolates electrical and battery compartments for more stable operation in dusty, hot climates.
PCS / MV Skid Ready
1500V DC output connects directly to a central PCS or pre-integrated MV skid up to 3.76MW — fewer transformers, faster grid connection.
MW-ESS7.53MWH-1500V — 7528.5kWh
One 40FT high-density platform: 18 liquid-cooled clusters of 314Ah LFP on a 1500V DC bus.
| Battery System | |
|---|---|
| Battery Type | Lithium Iron Phosphate (LiFePO4) |
| Cell Specification | 3.2V / 314Ah |
| Cluster Configuration | 18 × 1P416S |
| Nominal Capacity | 7528.5 kWh |
| Nominal Voltage | 1331.2 V |
| Battery Voltage Range | 1123.2 ~ 1497.6 V |
| Rated Charge/Discharge Rate | 0.5C |
| Round-Trip Efficiency | ≥ 94% |
| Cycle Life | ≥ 8000 cycles (@ 70% EOL) |
| General Data | |
|---|---|
| Cooling Method | Intelligent Liquid Cooling |
| Ingress Protection | IP55 (Battery Pack IP67) |
| Fire Protection | Pack-Level Detection + Aerosol Suppression |
| BMS Communication | CAN / RS485 / Ethernet |
| EMS Protocol | Modbus RTU / Modbus TCP |
| Operating Temperature | -30 ~ +55°C |
| Relative Humidity | 0 ~ 95%, Non-condensing |
| Altitude | ≤ 4,000 m |
| Dimension L×W×H | 12192 × 2438 × 2896 mm |
| Weight | About 55,000 kg |
| PCS Matching | |
|---|---|
| PCS Type | Central PCS / MV Skid (external) |
| PCS Power | Up to 3.76 MW (0.5C) |
| DC Input Voltage | 1500 V Platform |
| Standards | |
|---|---|
| Battery Standards | IEC 62619 / IEC 63056 / UL 1973 / UL 9540A / UN 38.3 |
| Installation Standard | NFPA 855 |
Specifications subject to change without notice.
What’s Inside the 40FT

- 1Battery Cabins18 liquid-cooled clusters of 314Ah LFP packs behind sealed cabin doors.
- 2Liquid-Cooling UnitsDoor-mounted chillers keep cell temperature deviation within ±3°C across all clusters.
- 3Electrical CompartmentDC combiner, cluster control boxes and BMS/EMS control in an independent bay.
- 4Fire Protection BayPack-level detection, aerosol suppression and pressure-relief venting at the container end.
Where the 40FT Delivers
Solar Farm Storage
Shift midday PV surplus to evening peaks and cut curtailment on utility-scale solar plants.
Frequency Regulation
Millisecond PCS response delivers primary frequency response and ancillary grid services.
Wind Integration
Smooth intermittent wind output and firm renewable delivery to the grid around the clock.
Microgrid & Island
Automatic on/off-grid switching and 110% long-term overload keep islanded loads online.
Industrial Park Peak Shaving
Reduce maximum demand charges with peak shaving, valley filling and dynamic transformer expansion.
Proven in the Field
40FT liquid-cooled containers at utility scale — video and photo records from real project sites.
Kindia 16MW+32MWh Solar-Storage Plant
Sixteen 40FT liquid-cooled containers form a 16MW/32MWh storage plant paired with a ground-mount solar farm in Kindia — the largest battery storage project in the region.
Riyadh Desert-Climate Storage Project
Two 40FT liquid-cooled containers run through 50°C desert summers outside Riyadh, firming a commercial solar plant with reliable backup when needed.

Atacama Utility-Scale Container Fleet
Rows of 40FT containers beside a substation in the Atacama Desert shift one of the world’s strongest solar resources into the evening peak.

Queensland Storage Plant Construction
Aerial view of a 90MWh 40FT container plant under construction in Queensland — crane lifts, pad works and grid connection in one coordinated build.
Standards & Certifications
Download the Catalog
Get the full Marwell Solar C&I BESS Catalog 2026 with the complete 40FT liquid-cooled container specifications, or send us your project requirements — our engineers will reply within 24 hours.





