P91-1.5kLi vs APC SMTL1500RM3UCNC
The P91-1.5kLi and APC SMTL1500RM3UCNC are both 1.5 kVA lithium UPS, on different architectures. The P91-1.5kLi is online double-conversion on LiFePO₄ batteries for zero-transfer-time operation and higher thermal tolerance; the APC is line-interactive lithium-ion with integrated management.
What the P91-1.5kLi brings
- Online double-conversion with zero transfer time
- LiFePO₄ chemistry, up to 15-year design life
- Longer runtime (7 min vs 5 min 6 s at full load)
- Faster recharge (1.5 h vs 2 h to 90%)
- 2U vs 3U – higher power density per rack unit
- TAA compliance and a 6-year warranty
Side-by-side specifications
| Specification | Xtreme Power P91-1.5kLi | APC SMTL1500RM3UCNC | Advantage |
|---|---|---|---|
| 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 | 1500 VA / 1350 W | 1500 VA / 1350 W | Equivalent output |
| High-temperature operation | Up to 50°C, derates above 40°C | Rated to 40°C | P91 – performs in higher heat |
| Recharge | 1.5 h to 90% | 2 h to 90% | P91 – faster recovery |
| Runtime (full load) | 7 min | 5 min 6 s | P91 – longer runtime |
| Rack height / depth | 2U / 16.1 in | 3U / 11.9 in | P91 – 2U vs 3U density |
| 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 P91-1.5kLi vs APC SMTL1500RM3UCNC comparison; confirm against current vendor documentation. The APC is 3U but shallower (11.9 in); the P91 is 2U but deeper (16.1 in, total with bezel).
Choosing between them
Equivalent on rated output. The P91-1.5kLi leads on topology, lifecycle, runtime, recharge, temperature, rack-unit density, and TAA; the APC is shallower (3U / 11.9 in) and includes network management by default.
Choose the P91-1.5kLi if you need
- Mission-critical IT and network infrastructure
- Edge sites with limited cooling and high heat
- Zero transfer time with longer runtime
- Federal / regulated procurement requiring TAA
The SMTL1500RM3UCNC may fit if you need
- General IT tolerant of line-interactive transfer time
- Integrated network management as standard
- Installations where rack depth matters more than height
Related comparisons
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.