P91 Li Lithium UPS (1000–3000VA, 120V) | Online Rack UPS

The P91 Li is a standard 2U lithium UPS designed for rack-based infrastructure where continuous conditioned power and predictable lifecycle performance are required.

It uses LiFePO₄ batteries to provide long service life, reduced maintenance, and stable operation in elevated temperature environments compared to traditional VRLA systems.

The platform is optimized for internal runtime and flexible deployment, making it well suited for standardized installations across multiple sites.

P91 Li is often evaluated alongside lithium rack UPS platforms such as APC Smart-UPS Ultra in standard rack deployments.

Key Specifications

• 1000 / 1500 / 2000 / 3000 VA
• 120V single phase
• Online double-conversion topology
• Lithium Iron Phosphate (LiFePO₄)
• Rack / tower / wall deployment
• Up to 50 °C operation (derating above 40 °C)
• Internal battery runtime
• 6-year warranty (U.S. & Canada)

Datasheet:
https://xpcc.com/p91-li-1-5-3kva-flyer/

Rack-Level Power Protection

P91 Li is deployed in distributed infrastructure environments where localized UPS protection is required at the rack level.

Online double-conversion topology provides zero transfer time and continuous conditioned power, isolating connected equipment from upstream disturbances.

Lithium battery architecture supports longer service intervals, improved thermal performance, and reduced maintenance compared to VRLA UPS systems.

Where P91 Li Fits

P91 Li operates as the standard lithium rack UPS platform within distributed infrastructure.

It is typically deployed:

• in network closets and IT racks
• in AV and security systems
• across multi-site distributed environments

Within the Xtreme Power architecture:

• J60C → short-depth lithium UPS
• P91 Li → standard lithium rack UPS (this platform)
• J90 → high-density lithium UPS
• P91 (VRLA) → extended runtime UPS

P91 Li vs High-Density Lithium UPS

P91 Li is designed for standard rack environments where internal runtime and flexible deployment are required.

Compared to high-density platforms such as J90:

• 2U form factor suited for conventional rack layouts
• internal runtime for ride-through and shutdown
• rack, tower, or wall installation

J90 is typically selected when:

• rack space is constrained (1U deployment)
• outlet-level switching is required
• extended runtime lithium configurations are needed

P91 Li vs Other Lithium Rack UPS Platforms

Feature	P91 Li	J90	APC SMTL Series	APC SRVSL Series	Eaton 9PX Lithium
Form Factor	2U	1U	2U / 3U (model dependent)	2U	2U
Topology	Online (double-conversion)	Online (double-conversion)	Line-interactive	Online	Online
Battery	LiFePO₄	LiFePO₄	Lithium-ion	Lithium-ion	Lithium-ion / LFP
Runtime	Internal	Internal + extended (2–3kVA)	Internal only	Internal	Internal + external
Individual Outlet Control	No	Yes (per outlet)	No	No	No
Temperature Rating	Up to 50°C	Up to 50°C	40°C typical	40°C typical	40°C typical
Deployment	Rack / tower / wall	Rack (1U)	Rack / tower	Rack / tower	Rack / tower
Positioning	Standard lithium UPS	High-density / premium	Legacy lithium	Value online lithium	Enterprise lithium

View detailed model comparisons →
https://xpcc.com/p91-li-ups-comparisons/

Lithium UPS Lifecycle Advantages

Lithium UPS systems provide lifecycle advantages compared to VRLA systems, including longer service life, improved thermal performance, and reduced maintenance requirements.

LiFePO₄ battery systems are designed for long lifecycle performance, with up to 15-year battery life under ideal operating conditions.

Learn more:
https://xpcc.com/lithium-ups-guide/

Rack Integration and Power Distribution

P91 Li is typically deployed with rack-mounted power distribution.

It pairs with intelligent PDUs such as the Xtreme Power SPDU platform (https://xpcc.com/products/spdu/) to enable outlet-level monitoring, control, and standardized rack power architecture.

Runtime Architecture

P91 Li uses an internal battery architecture designed for:

• short-duration ride-through
• controlled shutdown
• standardized deployment across multiple sites

It is not intended for long-duration runtime applications.

When to Use P91 Li

P91 Li is typically selected when:

• lithium UPS is preferred over VRLA
• internal runtime is sufficient
• standard rack deployment is required
• high-temperature environments are expected

Replace APC / Eaton Lithium UPS

P91 Li is commonly deployed as a replacement for lithium rack UPS systems from APC, Eaton, and Vertiv.

It provides a consistent lithium platform with predictable lifecycle performance and high-temperature operation up to 50 °C.

Explore comparisons:
https://xpcc.com/p91-li-ups-comparisons/

Typical Applications

P91 Li is deployed in:

• network closets and IT infrastructure such as IDF/MDF environments (https://xpcc.com/ups-for-idf-mdf-closets/)
• AV and security systems
• distributed edge and retail environments
• telecommunications infrastructure

It is particularly well suited for multi-site deployments where a consistent UPS platform is required.

Capacity Guidance

Capacity selection is based on load profile:

• 1000 VA → network switching and edge devices
• 1500 VA → small server and telecom nodes
• 2000 VA → distributed IT and AV systems
• 3000 VA → higher-density rack deployments

Technical Summary

• Topology: Online double conversion
• Capacity: 1000–3000 VA
• Voltage: 120V
• Battery: LiFePO₄ (internal)
• Form Factor: Rack / tower / wall
• Runtime: Internal
• Monitoring: Optional SNMP

Plan With Confidence

Xtreme Power Conversion supports UPS selection, lifecycle planning, and distributed infrastructure design for lithium rack UPS deployments.

(800) 582-4524
sales@xpcc.com