In the data center industry, uptime is not just a metric—it is a promise. Every system is engineered around redundancy, predictability, and risk elimination. From dual power feeds to advanced cooling design, infrastructure decisions are guided by one principle: avoid single points of failure.
Uninterruptible Power Supply (UPS) systems are central to this philosophy. When grid power fails, UPS batteries must respond instantly, reliably, and safely.
However, lithium-ion batteries introduce a variable that directly conflicts with uptime strategy: thermal runaway risk and high-consequence failure behavior.
For mission-critical facilities, uptime and lithium batteries simply do not mix.
The Core Problem: Unpredictable Failure
Lithium-ion batteries are valued for their high energy density and compact footprint. But in data center UPS environments, compact design is not the priority—predictability is.
Lithium-ion chemistry carries inherent risks:
- Thermal runaway under fault conditions
- Rapid temperature escalation
- Fire propagation between cells
- Violent failure modes
In a system designed to prevent cascading failure, this behavior is fundamentally incompatible.
Uptime requires controlled failure. Lithium-ion batteries do not fail quietly.
Thermal Runaway vs Infrastructure Stability
Thermal runaway is the most significant threat lithium batteries pose to uptime.
When one cell overheats due to internal defects, electrical faults, or high ambient temperature, it can trigger an uncontrollable chain reaction. Within seconds, adjacent cells may ignite.
In a UPS room, this can result in:
- Immediate shutdown of backup systems
- Fire suppression activation
- Forced facility evacuation
- Total service interruption
In other words, the very system designed to protect uptime becomes the source of downtime.
High Energy Density = High Impact Downtime
Lithium-ion batteries store a significant amount of energy in a small space. When failure occurs, the energy release is intense.
The consequences may include:
- Damage to battery cabinets and UPS systems
- Collateral impact on switchgear and power distribution
- Smoke contamination affecting IT equipment
- Extended restoration timelines
For colocation providers and enterprise data centers operating under strict SLAs, even minutes of downtime can translate into reputational and financial loss.
Uptime strategy is built around minimizing impact. Lithium-ion failure maximizes it.
Fire Suppression Is Not a Guarantee
Some operators assume that advanced fire suppression systems can mitigate lithium battery risks.
However, lithium-ion battery fires behave differently from standard electrical fires:
- They can generate their own oxygen
- They can reignite after being extinguished
- They spread rapidly through cell-to-cell heat transfer
This means suppression systems are reactive measures—not preventive solutions.
True uptime protection begins with eliminating technologies that allow uncontrolled escalation.
Uptime Requires Predictable Battery Behavior
For data centers, the ideal UPS battery must:
- Operate safely under elevated temperatures
- Fail in a controlled and isolated manner
- Avoid fire propagation between cells
- Deliver consistent standby performance over long service life
- Support sustainable lifecycle management
Stability, not density, should drive battery selection.
Increasingly, the industry is shifting toward battery technologies that eliminate thermal runaway risk and prioritize controlled behavior over compact design.
Uptime is built on predictability, redundancy, and controlled risk.
Lithium-ion batteries introduce thermal runaway potential, high-consequence failure modes, and fire propagation behavior that directly contradicts these principles.
For mission-critical data centers, the equation is simple:
If a battery technology can cause cascading failure, it does not belong in a zero-downtime environment.
Uptime and lithium batteries do not mix—because infrastructure resilience cannot depend on chemistry that behaves unpredictably under stress.
