Powering Encryption Key Retention with Long-Life Batteries

In the world of secure communications and cryptographic systems, protecting the encryption keys themselves is just as important as the cryptographic algorithms that use them. Whether in defense, aerospace, or high-security commercial applications, continuous power to volatile key memory is a foundational requirement—and it’s one of the toughest power challenges engineers face.

That’s where NanoTritium™ battery technology enters the conversation, offering long-life, maintenance-free power that can keep encryption keys alive for decades. In this post, we explore how battery-backed encryption key retention works, why traditional solutions fall short, and how tritium-based betavoltaic batteries are uniquely suited for secure key retention during power loss.

Encryption Keys and Volatile Memory: The Hidden Power Challenge

Encryption keys are the digital “locks” that protect sensitive information. In many cryptographic devices—particularly those built around field-programmable gate arrays (FPGAs) and secure processors—these keys are stored in volatile memory such as static random-access memory (SRAM).

SRAM is fast and secure, but it comes with a critical limitation: it requires continuous power. When power is removed, the stored keys disappear instantly. For cryptographic systems, that loss can result in:

• Failure of secure boot or authentication processes
• Loss of encrypted communications capability
• System lockout or degraded security posture

To mitigate this risk, many systems rely on battery-backed SRAM, using a dedicated power source to maintain encryption keys while the primary system is powered down. The effectiveness of this approach depends entirely on the reliability of that backup battery.

Why Conventional Batteries Fall Short

Traditional backup batteries rely on chemical reactions—and while they may work well for short-term applications, they introduce significant limitations for cryptographic devices expected to operate for decades.

• Limited lifespan: Chemical batteries degrade over time, often requiring replacement well before the system’s intended life.
• Environmental sensitivity: Performance drops sharply in extreme temperatures, vibration, or long idle periods.
• Maintenance burden: Replacing batteries in deployed or sealed systems can be expensive, disruptive, or impossible.

For applications that demand field-and-forget battery solutions and uninterrupted key retention, these shortcomings present unacceptable risk.

NanoTritium™ Batteries: Purpose-Built for Secure Key Retention

NanoTritium™ batteries take a fundamentally different approach to long-life power. Rather than relying on chemical reactions, they generate electricity through betavoltaic conversion, harvesting energy from the natural decay of tritium—a radioactive isotope of hydrogen.

This solid-state, micro-power nuclear battery design offers several advantages that align directly with cryptographic requirements.

Decades of Continuous Power

NanoTritium™ batteries are engineered to deliver reliable output for 20+ years. This makes them ideal for encryption key battery backup and volatile key memory backup in systems where maintenance access is limited or nonexistent.

Reliable Operation in Harsh Environments

Unlike chemical batteries, NanoTritium™ batteries maintain consistent performance across extreme temperatures and environmental conditions. This reliability is essential for cryptographic devices deployed in remote, industrial, aerospace, or defense environments.

Solid-State Safety and Compact Integration

With no liquid electrolytes or moving parts, NanoTritium™ batteries are inherently robust and compact. Their solid-state design enables seamless integration into cryptographic hardware without adding complexity or redesigning existing architectures.

Persistent Power for Battery-Backed SRAM

By supplying continuous micro-power to SRAM, NanoTritium™ batteries ensure secure key retention during power loss, preserving cryptographic state through shutdowns, resets, and extended downtime.

Proven Expertise: Supporting U.S. Air Force COMSEC Systems

City Labs’ expertise in encryption-key power security is not theoretical—it has been validated through real-world defense applications.

In 2024, City Labs was awarded a U.S. Air Force contract to develop a tritium-powered AA-format battery designed specifically to support communications security (COMSEC) devices. The goal: provide long-duration, maintenance-free power to cryptographic systems responsible for safeguarding sensitive military communications.

This program highlights several critical capabilities:

• Long-life battery support for cryptographic devices, reducing the risk of encryption key loss due to battery failure
• Continuous power for volatile encryption keys, even during extended power outages
• Improved COMSEC crypto key security, eliminating the need for frequent battery replacement or system access

The Air Force contract underscores the suitability of NanoTritium™ batteries for mission-critical encryption systems—and demonstrates City Labs’ leadership in solving one of the most persistent challenges in cryptographic hardware design.

Beyond Defense: Encryption Key Protection Across Industries

While defense and COMSEC systems represent some of the most demanding use cases, the same encryption-key power challenges exist across many commercial and industrial sectors:

• Secure communications infrastructure
• Encrypted industrial control systems
• High-assurance IoT and edge devices
• Aerospace and satellite platforms

As cryptographic devices become more distributed and harder to access, the importance of long-life, maintenance-free power sources continues to grow. In each of these applications, losing encryption keys due to power failure can compromise data integrity, system availability, and security compliance.

Powering the Future of Secure Systems

Encryption is only as resilient as the systems that support it—and in volatile memory architectures, the battery that maintains encryption keys is a core component of the security model.

By delivering 20+ years of continuous power, resisting harsh environments, and enabling true field-and-forget deployment, NanoTritium™ batteries provide a compelling solution for encryption key retention in both defense and commercial systems.

From battery-backed SRAM in secure processors to next-generation COMSEC platforms, NanoTritium™ technology ensures that encryption keys remain protected—even when everything else powers down.

To learn more about how City Labs can help power your needs, contact us today.