12V 4S 280-330Ah Battery Case

Universal battery case for 12V 4S LiFePO4 280-330Ah batteries with cell compression.

Made in Poland.

Battery case recognized at the ENEX 2025 Expo

• The case is a proprietary design by Onvolt, created in response to the wide range of LiFePO4 cells with capacities of 280-330Ah available on the market. These cells enable the construction of a compact and lightweight 12V energy storage system with parameters that, until recently, were only achievable by lead-acid batteries three times heavier and larger.
• The compact and robust design ensures a wide range of applications. The case is ideal for building energy storage systems for campers, mobile applications, as well as for residential use and holiday homes.
• Thanks to the clear and readable connection and control panel, you can easily make all electrical connections and monitor the operating parameters and battery state of charge.
• The high-quality 300A rotary switch provides additional protection when the battery is not in use.
• Dual 2x200A M8 current connectors enable convenient connection of receivers.
• The design of the case features a unique cell compression system that ensures the correct parameters for proper cell compression and efficient operation for many years. It is likely the only battery case on the market for four LiFePO4 cells that enables cell compression. At the same time, there is ample space inside the case to make safe electrical connections and properly route all wiring. There is also the option to install additional components inside the case, such as a battery separator for camper applications. We also ensured adequate airflow while maintaining sufficient case sealing for indoor operation.
• Both the case itself and the complete energy storage system can be easily transported thanks to convenient handles mounted on both sides. The use of suitable feet and optional mounting brackets allows the energy storage system to be placed freely anywhere, and in the case of applications in all types of vehicles, to be securely fixed to the floor.
• The case is designed for the JK 3-8S 200A BMS and optionally the JK 3.2″ LCD screen. For this configuration, ready-made connection kits (busbars, wires, fuse) are also available in versions for cells with M6 studs and with dual terminals.
• Made of aluminum, the case features high aesthetic value and is painted with a durable, resistant powder coating, ensuring excellent corrosion protection.
• The case is designed for four standard 280-330Ah LiFePO4 cells with dimensions of 175x72x205mm.

The box kit includes:

• The enclosure, including the cell mounting and compression mechanism.
• BMS mounting plate
• Side insulation plates 2 pcs.
• Upper and lower dielectric insulation plates (2 units).
• Bottom and rear rubber spacer
• Insulators 165×200 7pcs.
• 200A power connectors (+) and (-) – two sets
• 300A Rotary Switch
• Additional floor mounting brackets 2 pcs.
• Full hardware mounting kit (bolts, screws, and nuts).

The BMS, screen, cells, and the electrical connection kit for dual terminals or the electrical connection kit for screws are not included in the case kit and must be purchased separately.

• External dimensions of the housing LxWxH 390x180x295mm.
• Weight of empty case approx. 2 kg