Case Study: Army CombatConnect — Solving the Soldier Power Problem

The modern infantry soldier carries more electronics than at any point in military history. A fully equipped US Army infantry soldier in a peer-conflict scenario may carry a personal radio, GPS tracker, helmet-mounted camera, night-vision system, weapon-mounted thermal sight, biometric health monitor, and a handheld mission terminal. Each of these devices has historically carried its own battery — its own chemistry, its own charge state, its own logistics tail.

The cumulative effect is a soldier carrying 10–20 kg of batteries on a 72-hour mission, alongside ammunition, food, water, and medical supplies — a total load that routinely exceeds 60 kg and creates physiological stress that degrades performance, increases injury risk, and limits operational endurance.

The US Army Program Executive Office (PEO) Soldier’s CombatConnect programme represents the most comprehensive effort to date to redesign the power architecture for the dismounted soldier — replacing distributed individual batteries with a shared power bus, managed centrally from the plate carrier, and governed by intelligent load management software.

The Problem: Battery Proliferation and Its Consequences

The battery management burden

Before CombatConnect, and in units not yet equipped with its successors, every device a soldier carries has an independent power source. This creates a cognitive and logistics burden that is easy to underestimate:

• Different chemistries: Some devices use AA alkaline, others use 18650 Li-ion, others proprietary packs, others USB-C rechargeable cells. There is no single battery that serves all.
• Different charge states: Each device depletes at a different rate depending on use. A soldier monitoring radio communications discharges the radio faster than a soldier in noise discipline.
• Failure modes are silent: A device that has silently discharged during a long patrol may fail at exactly the moment it is needed. The soldier may not know it is dead until the critical moment.
• Logistics multiplication: Different battery types require different resupply chains. Forward logistics elements must stock and distribute multiple battery types. A shortage of one type cannot be compensated by a surplus of another.

The weight problem

Studies of soldier electronics power loads consistently show batteries as a significant fraction of total carried weight. In a 72-hour mission with full electronics usage, battery weight may reach 15–20% of total pack weight. This is weight that could otherwise be allocated to:
– Additional ammunition (direct combat effectiveness)
– Medical supplies (force protection)
– Water and food (endurance)
– Reduced total load (mobility, injury prevention)

The thermal signature problem

Every battery is a thermal mass. In cold-weather operations, individual batteries pressed against the body can cause localised discomfort and thermal injury. In warm-weather operations, warm batteries contribute to the soldier’s heat load. Centrally managed power from a thermally optimised pack addresses both.

The CombatConnect Solution: A Shared Power Bus in the Plate Carrier

CombatConnect, developed by US Army PEO Soldier, is a smart power distribution hub integrated into the soldier’s plate carrier (body armour). Rather than each device carrying its own battery, all devices receive power from a single centralised energy source — a large-capacity lithium-ion battery pack mounted in the plate carrier — through a managed bus.

System architecture

┌─────────────────────────────────────────────────────────────┐
│  Central Battery Pack (Plate Carrier Integrated)            │
│  • High-capacity Li-ion (target: 72-hour mission endurance) │
│  • Battery management system (BMS)                          │
│  • Smart charge controller                                  │
└─────────────────────────────┬───────────────────────────────┘
                              │
┌─────────────────────────────▼───────────────────────────────┐
│  CombatConnect Smart Hub                                    │
│  • Embedded processor (power management and data routing)   │
│  • Per-port power measurement and control                   │
│  • Device identification and compatibility checking         │
│  • Intelligent load shedding under low battery conditions   │
│  • Data aggregation bus (device telemetry to hub)           │
└──────┬──────────┬──────────┬──────────┬──────────┬──────────┘
       │          │          │          │          │
   Radio       GPS       Camera     Health      Weapon
   port        port      port       monitor     sight
                                    port        port

Key capabilities of the CombatConnect hub:
– Per-port power control: the hub can power individual device ports on or off, enabling automatic power-off of non-essential devices under low battery conditions
– Device identification: the hub identifies connected devices and applies appropriate power profiles (voltage level, current limit) for each device type
– Power monitoring: the hub measures real-time power consumption by device, enabling the soldier or commander to see which device is consuming the most power and manage accordingly
– Data integration: devices connected to the CombatConnect bus can report status data (battery level, operational status, sensor readings) to the hub, which aggregates and uplinks to the platoon network

Power budget benefits

Elimination of redundant battery overhead: When every device carries its own battery, each battery is sized for the worst-case consumption of that device for the full mission duration. But devices are not all at maximum consumption simultaneously — a device in standby consumes a fraction of its peak draw. With a shared pool, the total battery capacity needed is significantly less than the sum of individual worst-case capacities.

Example calculation:

In this simplified example, shared pool architecture reduces the required battery capacity from 455 Wh to approximately 183 Wh — a 60% reduction in battery energy (and proportional reduction in battery mass and volume), while delivering the same 72-hour mission capability.

Actual reductions of 30–40% in total battery weight have been cited in US Army programme documentation, reflecting the real-world utilisation patterns of deployed systems.

Standards Compliance for Soldier-Worn Power Systems

CombatConnect is designed and tested to the environmental standards applicable to dismounted infantry equipment:

MIL-STD-810H

Method 501.7 (High Temperature): Operation at +49 °C ambient — representing operations in desert environments. The hub and battery pack must manage thermal dissipation to prevent lithium battery thermal events under sustained high-power draw in hot conditions.

Method 502.7 (Low Temperature): Operation at −40 °C (extended cold requirement). Lithium-ion cells lose significant capacity below −20 °C. The CombatConnect battery pack incorporates a thin-film resistive heater that warms the cells to an operable temperature before high-current draw, activated by the BMS at startup.

Method 506.6 (Rain) / Method 512.6 (Immersion): The hub and connectors must meet IP67 minimum — rain, river crossing, and mud immersion are expected operational scenarios for infantry. Military-spec circular connectors (MIL-DTL-38999 or equivalent) are used at all device interface points.

Method 514.8 (Vibration) / Method 516.8 (Shock): The plate carrier undergoes continuous vibration from running, jumping, and vehicle transport, as well as shock events from falls, near-miss blast, and hard landings. The hub must survive these events without damage or connector disconnection.

MIL-STD-461G

The CombatConnect hub, as an active electronics assembly, must meet MIL-STD-461G EMC requirements to ensure it does not interfere with the soldier’s radio systems:

• CE102: Conducted emissions on the power distribution bus must not inject RF noise into the radio’s power supply at levels that would degrade receive sensitivity
• RE102: Radiated emissions from the hub’s switching regulators must not interfere with the GPS receiver’s L1/L2 frequency bands (1.2–1.6 GHz) or the radio’s operating frequencies
• CS116: The hub must survive voltage transients on its power inputs without damage or lockup

DEF STAN 00-35 (UK compatibility)

For UK, Australian, Canadian, and other NATO nation procurement of compatible systems, DEF STAN 00-35 environmental qualification provides documentation compatible with UK MoD and allied procurement processes. The test conditions of DEF STAN 00-35 Parts 2 and 3 (climatic and mechanical) are broadly equivalent to MIL-STD-810H for dismounted infantry equipment.

Energy Harvesting: The Next Step Beyond Battery Sharing

CombatConnect in its current form still requires that the central battery be carried and charged before each mission. The next generation of soldier power research, funded by US DoD, addresses this through in-mission energy harvesting — recovering energy from the soldier’s own activity to extend or eliminate the need for carried batteries.

Kinetic energy harvesting

Infantry soldiers expend significant mechanical energy during operations — approximately 300–400 W of metabolic power during moderate-intensity movement, of which 1–10% is potentially harvestable through non-obtrusive means:

• Heel-strike harvesters: Piezoelectric or electromagnetic generators embedded in boot soles, recovering energy from the impact and compression of each step. Research prototypes have demonstrated 1–5 W of recovered power during sustained walking.
• Knee energy harvesters: Devices that capture the negative work performed by the knee during the braking phase of the stride (deceleration phase), where the leg muscles act as brakes. The Bennet system and similar devices have demonstrated 5–7 W of recovered power during walking without measurable metabolic cost increase.
• Backpack suspension harvesters: Vertical displacement of the pack relative to the frame during walking can drive a linear generator. The “lightning pack” concept demonstrated 7.4 W of recovered power.

At 5 W of continuously harvested power, the daily energy recovery is 360 Wh — exceeding the estimated shared pool requirement calculated above, and potentially enabling the elimination of carried primary batteries for the electronic load during sustained operations.

Thermal energy harvesting

The human body maintains a core temperature of approximately 37 °C. In cold ambient conditions, a temperature differential exists between skin surface and ambient air. Thermoelectric generators (TEGs) convert this temperature gradient directly to electricity. At skin temperature (35 °C) and ambient temperature of 5 °C (30 °C differential), a wearable TEG can generate approximately 30–50 mW/cm² — sufficient to power low-power biometric sensors and short-range radios without any carried battery contribution.

Data Integration: The Tactical Hub Beyond Power

CombatConnect is not only a power distribution system — it is a data aggregation hub. Devices connected to the CombatConnect bus expose sensor data, status information, and telemetry to the hub, which aggregates and processes this data and uplinks it to the platoon network.

Practically, this means:

• Health monitoring data (heart rate, temperature, hydration indicators) from the biometric monitor flows through the hub to the platoon medic’s display in real-time, enabling remote casualty assessment
• Position data from the GPS tracker is shared with the platoon position display without the soldier needing to operate a separate reporting device
• Radio status (frequency, battery level, receive signal strength) is visible to the communication officer
• Weapon sight video can be uplinked through the hub’s data bus to the squad leader’s display during close-quarters engagement

This creates a body-area network (BAN) in which the CombatConnect hub serves as the edge computing and communications node for all soldier electronics — a direct implementation of the Body Sensor Network architecture described in research literature and in Post 2 of this series.

Broader Implications: The Wearable IoT Platform for Soldiers

CombatConnect represents a maturation of the soldier electronics ecosystem from a collection of independent devices into an integrated soldier IoT platform. Each device is no longer standalone — it is a node on the body-area network, sharing power and data through the hub.

This architectural shift has parallels far beyond military applications:

• Industrial wearables: Worker safety monitoring in hazardous environments (mining, offshore, chemical plants) faces the same challenge of powering multiple wearable sensors from a single source while managing data from all sensors through a single uplink
• Emergency responder equipment: Firefighters, paramedics, and search and rescue personnel carry multiple electronic devices under similar constraints — weight, battery duration, environmental protection — and face similar data integration challenges
• Remote monitoring in infrastructure: The store-and-forward, duty-cycled, shared power architecture of CombatConnect’s data bus reflects principles directly applicable to multi-sensor monitoring nodes in water, energy, and building infrastructure — ThingsLog’s core commercial market

Conclusion: Convergence of Military and Commercial IoT Design

CombatConnect illustrates a principle that runs throughout this series: the engineering requirements of military electronics and advanced commercial IoT are not as far apart as they might appear. Both are driven toward:

• Ultra-low standby power consumption
• Intelligent duty cycling of high-power subsystems
• Local data buffering and store-and-forward communication
• Shared power architectures that optimise total energy budget
• Extreme environment survival and IP67+ ingress protection
• Ruggedised, lightweight enclosures with military-spec connectors

The difference is in the certification framework (MIL-STD-810H, MIL-STD-461G, NATO STANAG 4370) and the component qualification requirements (MIL-PRF-38535). The underlying engineering principles are shared.

ThingsLog develops ultra-low-power IoT hardware at the intersection of these requirements — platforms that are engineered for the extreme environment performance that military applications demand, while remaining accessible for the wide range of civilian and defence-adjacent monitoring applications where these capabilities matter most.

Contact ThingsLog to discuss how our monitoring platform can address your requirement for long-life, rugged, low-power sensing in demanding environments.

Sources

• US Army CombatConnect — PEO Soldier Programme
• Military Wearables Enhance Soldier Capabilities — Connector Supplier
• Soldier Wearable Technologies Advance Military Operations
• Systematic Analysis of a Military Wearable Device — PMC
• Wearables for Defense: The Next Frontier — Sensio AI
• How Military Wearables Are Revolutionising Soldier Technology — Elitac Wearables

Series Navigation

• Why Low Power Matters in Military Operations
• Key Application Domains
• How Military Low-Power Electronics Are Built
• Protective Coatings for Military Electronics
• Military Electronics Standards
• IP Ratings and Ingress Protection
• Case Study: DARPA N-ZERO
• Case Study: LoRa Tactical Troop Tracking
• Case Study: ThingsLog LPMDL in Antarctica
• Case Study : Army CombatConnect