P91-1kLi vs APC SMTL1000RM2UCNC
The P91-1kLi and APC SMTL1000RM2UCNC are both 1 kVA lithium UPS for IT, network, and edge deployments, but on different platforms. The P91-1kLi is a true online double-conversion UPS on LiFePO₄ batteries with zero transfer time; the APC is a line-interactive lithium-ion UPS with integrated network management.
What the P91-1kLi brings
- Online double-conversion with zero transfer time
- LiFePO₄ chemistry, up to 15-year design life
- Higher usable real power (900 W vs 800 W)
- Operation up to 50 °C with derating above 40 °C
- Shallower depth and wall-mount flexibility
- TAA compliance and a 6-year warranty
Side-by-side specifications
| Specification | Xtreme Power P91-1kLi | APC SMTL1000RM2UCNC | Advantage |
|---|---|---|---|
| Availability | August 2026 | Current production | P91 – next-generation platform |
| Battery chemistry | LiFePO₄ | Lithium-ion | P91 – longer cycle life |
| Battery life | Up to 15 yr / 3,000–5,000 cycles | 8–10 years typical | P91 – longer service life |
| Topology | Online double-conversion | Line-interactive | P91 – zero transfer time |
| Capacity | 1000 VA / 900 W | 1000 VA / 800 W | P91 – higher usable watts |
| High-temperature operation | Up to 50°C, derates above 40°C | Rated to 40°C | P91 – edge / light-industrial |
| Runtime (full load) | 6 min 36 s (at 900 W) | 7 min 47 s (at 800 W) | P91 carries higher load |
| Rack height / depth | 2U / 11.6 in | 2U / 12.5 in | P91 – shallower depth |
| Form factor | Rack / tower / wall | Rack / tower | P91 – adds wall mount |
| Network management | Optional Web/SNMP (SNMP-2PV3) | Integrated network management | APC – integrated by default |
| TAA compliance | Yes | No | P91 – federal procurement |
| Warranty | 6-year UPS & battery | 5-year UPS & battery | P91 – longer coverage |
Specifications from Xtreme Power’s supplied P91-1kLi vs APC SMTL1000RM2UCNC comparison; confirm against current vendor documentation. Depth is total (with bezel); the datasheet’s 10.6 in is bracket-to-panel. Availability shown as August 2026 per current guidance (source sheet said June 2026).
Choosing between them
Both are compact 1 kVA lithium rack UPS. The P91-1kLi adds full online double-conversion, LiFePO₄ lifecycle, higher usable watts, 50°C operation, shallower depth, and TAA; the APC includes network management by default and runs slightly longer at its lower 800 W rating.
Choose the P91-1kLi if you need
- Edge IT and network closets with limited cooling
- Zero transfer time and clean conditioned output
- Higher usable watt capacity in a compact UPS
- Government / regulated procurement requiring TAA
The SMTL1000RM2UCNC may fit if you need
- General IT tolerant of line-interactive transfer time
- Integrated network management out of the box
- Deployments where 800 W is sufficient
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Standardizing on lithium rack UPS?
Xtreme Power supports UPS selection, lifecycle planning, and distributed infrastructure design for lithium rack UPS across IT, networking, and regulated environments.