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

1000–3000 VA | 120V | Online Double-Conversion UPS

Lithium rack UPS designed for distributed IT, network, and AV infrastructure requiring reliable power protection, long battery life, and standardized deployment.


1000–3000 VA · 120VAC · Online Double-Conversion Lithium Rack UPS

P91 Li lithium online rack UPS

The P91 Li is a 2U online double-conversion UPS built on lithium iron phosphate (LiFePO₄) batteries for rack-based infrastructure that needs continuous conditioned power and predictable lifecycle performance. Online topology delivers zero transfer time and full isolation from upstream disturbances, while LiFePO₄ chemistry adds long service life, reduced maintenance, faster recharge, and stable operation up to 50 °C. Rack, tower, or wall mountable and TAA-compliant, it is designed for standardized deployment across distributed IT, network, and AV sites — including a new short-depth 1000 VA model for shallow racks.

1000–3000
VA (900–2700 W)
Online
Double-conversion
LiFePO₄
Lithium iron phosphate
2U
Rack / tower / wall
50°C
High-temp operation
6-year
Warranty (US & Canada)

Xtreme Power P91 Li 2U online double-conversion lithium rack UPS, front view with status LCD

P91 Li 2U online double-conversion lithium UPS — front view with status LCD.

Overview

Rack-level power protection

The P91 Li is deployed in distributed infrastructure 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.

LiFePO₄ technology delivers up to 15 years of battery life — up to four times longer than lead-acid — eliminating routine replacement cycles, while internal runtimes run up to five times longer than comparable lead-acid systems and recharge to 90% in about 1.5 hours.

Key features

What the P91 Li delivers

Topology

Online double-conversion

Zero transfer time and the cleanest output – pure sine wave at ≤2% THD (linear) / ≤4% THD (non-linear).

Lithium

LiFePO₄ long life

Up to 15-year battery life or 3,000–5,000 discharges, eliminating routine battery replacement.

Thermal

50 °C operation

Rated for high-temperature environments up to 50 °C (122 °F), with derating above 40 °C.

Serviceability

Hot-swappable battery + BMS

Hot-swappable internal lithium pack; the battery management system guards over-voltage, over-current, and over-temperature.

Assurance

6-year warranty + $50,000 policy

Six years on electronics and battery, plus a $50,000 connected-equipment load-protection policy.

Efficiency

Light, efficient, fast recharge

About 30% lighter than typical lead-acid; up to 98% ECO / 94% online efficiency; 1.5 h recharge to 90%.

Where the P91 Li fits

The standard lithium rack platform

The P91 Li operates as the standard lithium rack UPS within the Xtreme Power architecture — deployed in network closets, IT racks, AV systems, and multi-site environments where a consistent platform is required. It sits between compact lithium platforms such as the J60C and high-density platforms such as the J90, balancing flexibility, runtime, and standard rack deployment.

Xtreme Power lithium UPS architecture

Compact lithium
J60
Device-level lithium UPS

View J60 →

1U short-depth lithium
J60C
Compact rack lithium

View J60C →

Online rack lithium · this platform
P91 Li
2U online double-conversion

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High-density lithium
J90
Outlet switching, extended runtime

View J90 →

Three-phase lithium
Li90
10–30 kVA online

View Li90 →

P91 Li vs high-density lithium

P91 Li or J90?

The P91 Li is designed for standard rack environments where internal runtime and flexible deployment are required, in a 2U form factor suited to conventional racks with rack, tower, or wall installation. The J90 is typically selected when rack space is constrained, outlet-level switching is required, or extended-runtime lithium configurations are needed.

Need outlet-level switching, a denser footprint, or extended external runtime? Compare the high-density J90.

J90 comparisons →

Model selection

Four models, 1000–3000 VA

Model Capacity Receptacles Line cord Dimensions (W×D×H) Weight Battery config
P91-1kLi (short-depth) 1000 VA / 900 W (8) NEMA 5-15R 6 ft, 5-15P 17.2 × 10.6 × 3.4 in 17.2 lb 8S2P
P91-1.5kLi 1500 VA / 1350 W (8) NEMA 5-15R 6 ft, 5-15P 17.2 × 15.1 × 3.4 in 25.6 lb 15S2P
P91-2kLi 2000 VA / 1800 W (8) NEMA 5-15/20R 6 ft, 5-20P 17.2 × 19.0 × 3.4 in 33.5 lb 15S2P ×2
P91-3kLi 3000 VA / 2700 W (1) L5-30R + (6) 5-15/20R 6 ft, L5-30P 17.2 × 23.8 × 3.4 in 45.2 lb 24S1P ×3

All models are 2U (3.4 in) high and 17.2 in wide; depth grows with capacity (the 1000 VA model is short-depth at 10.6 in). Rack depth is measured front bracket to unit panel; add 1 in for the front bezel. Output voltage is selectable (100 / 110 / 115 / 120 / 127 VAC); derate capacity to 80% at 100 VAC.

The short-depth P91-1kLi (1000 VA / 900 W) ships August 2026 — a 10.6-inch-deep 2U chassis that brings online lithium protection to shallow racks and wall cabinets.

P91 Li datasheet →

Battery runtimes

Internal battery runtime by load

Model 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
P91-1kLi 67 38 27 20 16 13 11 9 7.5 6.6
P91-1.5kLi 101 49 31 23 17 15 12 10 8 7
P91-2kLi 148 72 46 35 27 22 19 16 15 13
P91-3kLi 115 56 36 26 21 17 15 13 11 10

Runtimes in approximate minutes at each percentage of rated load, on internal batteries. Actual runtime varies with battery age, temperature, and load. The P91 Li is designed for short-duration ride-through and controlled shutdown, not long-duration runtime. Size it with the UPS selector →

Applications

Built for distributed rack infrastructure

The P91 Li is deployed across network closets, AV systems, telecommunications infrastructure, and distributed IT — particularly IDF/MDF deployments and multi-site infrastructure where a consistent, maintainable UPS platform is required.

Networking

Network closets

Conditioned power for switching, routing, and edge network equipment.

IDF / MDF

Distribution closets

A consistent lithium platform for IDF/MDF and structured cabling rooms.

Pro AV

AV systems

Clean, zero-transfer power for AV racks and control systems.

Telecom

Telecommunications

Reliable ride-through for telecom and communications nodes.

Edge IT

Distributed IT

Standardized rack protection across distributed and edge sites.

Multi-site

Multi-site rollouts

Predictable lifecycle and maintenance for repeatable deployments.

Capacity guidance: 1000 VA (short-depth) for network switching and edge devices; 1500 VA for small server and telecom nodes; 2000 VA for distributed IT and AV systems; 3000 VA for higher-density rack deployments.

Technical specifications

P91 Li specifications

Specification Detail
Topology Online double-conversion
Capacity 1000 / 1500 / 2000 / 3000 VA (900 / 1350 / 1800 / 2700 W)
Input 55–150 VAC (load dependent), 50/60 Hz auto-sensing
Output voltage 100 / 110 / 115 / 120 / 127 VAC selectable (derate to 80% at 100 VAC)
Output waveform Pure sine wave; ≤2% THD (linear), ≤4% THD (non-linear)
Output frequency 50/60 Hz ± 0.1 Hz
Efficiency Up to 98% (ECO mode) / 94% (online mode)
Overload (online) 110–130% for 5 min; >130–140% for 30 s; >140% for 1.5 s
Battery LiFePO₄ — LFP256000 (1000 VA) / LFP26650 2600 mAh (1500–3000 VA); hot-swappable internal pack
Battery life Up to 15 years / 3,000–5,000 discharges
Recharge 1.5 h to 90% (1500–3000 VA) or 3 h (1000 VA); charger 2/4/6/8 A (4 A default) or 1.5 A (1000 VA), LCD-adjustable
Form factor 2U; rack, tower, or wall mount (1000 VA is short-depth, 10.6 in)
Operating temperature 32–122°F (0–50°C), derating above 104°F (40°C)
Altitude Up to 6,500 ft
Communications RS-232, USB, EPO; intelligent slot (Web/SNMP, relay/dry contact, Modbus)
Approvals UL, cUL, RoHS, FCC Class A; battery packs UL1973, UN38.3; TAA compliant
Load protection policy $50,000 connected-equipment protection
Warranty 6-year electronics / 6-year battery (USA & Canada)
Included ViewPower software, front brackets, tower pedestals, user manual
Options Switched metered-by-outlet PDU (SPDU), bypass distribution (XBDM), 4-post rail kit, 2-post shelf kit, wall-mount bracket

A 2-year warranty applies where ambient temperature exceeds 40°C (104°F) and is below 50°C (122°F). Confirm configuration-specific details on the datasheet.

Rack integration

Power distribution and monitoring

The P91 Li is typically deployed with rack-mounted power distribution and integrates with intelligent PDUs for monitoring and control. It pairs with Xtreme Power SPDUs to support standardized rack power architecture, remote monitoring, and outlet-level control across distributed deployments.

Xtreme Power P91 Li mounted in a rack above an XBDM bypass distribution module

P91 Li paired with the XBDM bypass distribution module in a rack.

Add outlet-level monitoring and switching with a switched, metered-by-outlet SPDU.

Smart PDU →

Lithium lifecycle

Lifecycle advantages over VRLA

Lithium UPS systems provide lifecycle advantages over VRLA, including longer service life, improved thermal performance, and reduced maintenance. LiFePO₄ battery systems are designed for long lifecycle performance, with up to 15-year battery life under ideal operating conditions.

Understand lithium chemistry, lifecycle, and deployment trade-offs.

Lithium UPS guide →

Plan with confidence

Xtreme Power supports UPS selection, lifecycle planning, and distributed infrastructure design for lithium rack UPS deployments across network, AV, telecom, and multi-site environments.

MODEL NUMBER P91-1.5kLi P91-2kLi P91-3kLi
CAPACITY Power rating 1500VA (1350W) 2000VA (1800W) 3000VA (2700W)
INPUT Voltage/frequency     55–150VAC* /  50/60Hz auto-sensing
OUTPUT Voltage 100**/110/115/120/127 VAC selectable
Waveform Pure sine wave: <=2% THD (linear load), <=4% THD (non-linear load
Frequency 50/60Hz ± 0.1Hz
Efficiency Up to 98% ECO mode or 94% online mode
Overload capacity Online mode: 110% & ≤ 130% for 5 min; > 130% & ≤140% for 30 sec; >140% for 1.5 sec
BATTERY Cell type LFP26650 2600 mAh
Cell configuration 15S2P 15S2P x2 24S1P x 3
Charger voltage 52.5VDC 84VDC
Charger current 2/4/6/8A (4A default), adjustable through LCD
Recharge time 1.5 hours to 90% charge
PHYSICAL Dimensions (W x D x H)*** 17.2 x 15.1 x 3.5 17.2 x 19 x 3.5 17.2 x 23.8 x 3.5
Weight (lbs) 25.6 33.5 45.2
Line cord 6 ft, 5–15P 6 ft, 5–20P 6 ft, L5–30P
Receptacles (8) NEMA 5-15R (8) NEMA 5–15/20R L5–30R+(6)5–15/20R
ENVIRONMENT Operating temperature 32–104°F (0–40°C)
Altitude 11,500 ft above sea level
APPROVALS UL, cUL, RoHS, FCC Class A, battery packs comply to UL1973, UN38.3, TAA compliant
WARRANTY 6 years electronics, 6 years battery warranty (USA and Canada)
COMMUNICATIONS INTERFACE RS-232, USB, EPO, intelligent slot for optional cards (Web/SNMP, Relay/dry contact, Modbus)
INCLUDED IN BOX ViewPower software, front brackets, tower pedestals, user manual
AVAILABLE OPTIONS Bypass distribution (XBDM), power distribution (XPDU), 4-post rail kit, 2-post shelf kit, wall mount bracket