Patented junction enables modular field power

Custom Electronics has received a patent for a DC power-junction architecture that allows several energy sources to operate in parallel without discharging into one another.

The source-agnostic system can connect batteries, solar equipment, and other DC supplies, while individual sources can be hot-swapped without interrupting power from the remaining units. Preventing cross-discharge protects sources that differ in state of charge, voltage, internal resistance, age, temperature, or chemistry.

An uncontrolled direct parallel connection can create substantial equalisation currents, placing stress on cells, cabling, connectors, contactors, and protection devices. The patented junction controls the relationship between the sources while maintaining a shared output to the connected equipment.

The technology is incorporated into the CMP2500 modular battery platform. Each lithium iron phosphate module provides 2.5kWh, while four units can be combined to supply up to 10kWh at 24VDC.

Battery modules and the central junction are housed in rugged transportable cases designed to be moved by one person. Applications include drone charging, training simulations, target systems, silent-watch operations, and other military or industrial loads operating away from fixed electrical infrastructure.

The platform includes a proprietary battery-management system, inverter options providing up to 4,000W, and chargers rated at up to 40A DC. Voltage and capacity can be adapted for different installations, while modular packs allow depleted units to be exchanged during operation.

Hot-swapping at meaningful power levels requires controlled contact sequencing, pre-charge, arc suppression, and verification that the incoming source sits within an acceptable voltage range. A robust connector alone cannot prevent damaging inrush or interruption when a charged module is introduced to an energised bus.

The junction addresses the flow between sources, while the complete system must still manage short circuits, reverse polarity, ground faults, overtemperature, connector damage, and safe isolation during maintenance. Fuse coordination and conductor sizing must account for the combined fault current available from every connected module.

Field systems become managed DC networks

Remote military and industrial equipment is drawing more electrical power as uncrewed vehicles, communications, sensing, computing, surveillance, and electronic-warfare systems become more capable. Those loads may operate continuously even where a generator is undesirable or cannot be run efficiently.

Combustion generators remain flexible, although they introduce fuel logistics, maintenance, noise, exhaust, heat, and periods of inefficient low-load operation. A battery system can carry silent or intermittent loads, allowing the generator to run less frequently and closer to an efficient operating point when charging is required.

Storage does not remove the charging requirement, since mission duration remains constrained by available energy, temperature, battery health, charger power, and replenishment time. It instead changes when generation is needed and allows several supply types to be combined around a managed DC bus.

Power quality is particularly important where sensitive communications, computing, and sensing equipment share the same source as motors, chargers, or switching converters. Military EMI and transient filters designed for high-power DC systems illustrate the protection required between a field energy source and equipment vulnerable to conducted noise or surge events.

Battery identity and history become more important as modules circulate between chargers, missions, and equipment sets. Cycle count, state of health, cell batch, firmware revision, fault records, and maintenance history can determine whether packs with similar terminal voltages should be connected together.

The same evidence chain begins during manufacture, where cell, interconnect, process, calibration, and firmware records are increasingly linked. Modular field systems extend that traceability into operation because usage history directly affects available capacity and reliability.

Lithium iron phosphate provides strong cycle life and comparatively stable thermal behaviour, although it still requires cell monitoring, balancing, temperature supervision, and fault protection. Transportable enclosures must combine mechanical restraint, environmental sealing, ventilation, and access without trapping heat around the cells or conversion hardware.

Mixed-source operation also requires clear grounding and isolation rules. Solar input, vehicle power, chargers, inverters, and load equipment may each introduce a different connection to chassis or earth, creating circulating currents or unexpected fault paths when joined without a defined architecture.

The CMP2500 demonstrates the patented junction within a practical modular system rather than as a standalone circuit. Its wider application could extend into emergency power, temporary infrastructure, mobile laboratories, remote industrial equipment, and renewable-energy installations combining several DC sources.

Field power is moving from a single generator and distribution box towards networks of storage, generation, conversion, monitoring, and protected loads. The junction provides one of the control points needed for that transition, while reliable deployment will depend on the protection, thermal management, connectors, and operating procedures built around it.