Li90 vs E91
The Li90 and E91 are both Xtreme Power online double-conversion three-phase UPS platforms with integrated maintenance bypass. They are optimized for different priorities: the E91 covers a wider capacity range including larger kVA, while the Li90 is engineered for longer runtime, higher operating temperature, and reduced maintenance through lithium iron phosphate batteries. The right choice depends on capacity, runtime, temperature, and maintenance priorities.
Li90 and E91 at a glance
- Li90: lithium (LFP), longer internal runtime, 50 °C operation, hot-swap modules
- E91: VRLA, wider capacity range to 40 kVA, conventional well-cooled installations
- Li90: up to 5-year battery warranty; E91: 2-year
- Both: online double conversion with integrated maintenance bypass
Side-by-side specifications
| Specification | Xtreme Power Li90 | Xtreme Power E91 | Positioning |
|---|---|---|---|
| Topology | Online double conversion | Online double conversion | Equivalent protection |
| Available capacities | 10 / 20 / 30 kVA | 10 / 15 / 20 / 30 / 40 kVA | E91 reaches 40 kVA; Li90 to 30 |
| Battery technology | Lithium iron phosphate (LFP) | VRLA (lead-acid) | Li90 lithium; E91 VRLA |
| Internal runtime at full load | 15–45 min | 7–11 min | Li90 longer internal runtime |
| Battery life | Up to 10 yr / approx 2,000 cycles | 3–5 yr / approx 300 cycles | Li90 longer battery life |
| Battery replacement | Hot-swappable lithium modules | Not hot-swappable | Li90 hot-swappable |
| Operating temperature | Up to 50 °C (122 °F) | Up to 40 °C (104 °F) | Li90 to 50 °C |
| Maintenance bypass | Standard | Standard | Both standard |
| Battery warranty | 5 years (LFP) | 2 years (VRLA) | Li90 longer battery warranty |
Both are Xtreme Power platforms; this comparison is for selecting between them. Specifications from current product documentation. Note: Li90 battery design life is stated here as up to 10 years; confirm against the Li90 datasheet, which lists up to 15 years on some materials.
Choosing between them
Both are Xtreme Power online double-conversion platforms. The Li90 (lithium) is built for longer internal runtime, 50 °C operation, hot-swap service, and reduced maintenance; the E91 (VRLA) covers a wider capacity range to 40 kVA for conventional, well-cooled installations. The right choice depends on capacity, runtime, temperature, and maintenance priorities.
Consider the Li90 for
- Long internal runtime without external batteries
- Lithium battery technology with extended service life
- Operation in environments up to 50 °C
- Hot-swappable batteries to minimize maintenance downtime
- Lower long-term battery replacement and service costs
Consider the E91 for
- A wider range of kVA sizes up to 40 kVA
- A traditional VRLA-based online UPS architecture
- Standard data center conditions with controlled cooling
- Sites planning external battery cabinets for extended runtime
Frequently asked questions
Both are Xtreme Power online double-conversion three-phase UPS. The E91 (VRLA) offers a wider capacity range up to 40 kVA for conventional, well-cooled installations; the Li90 (lithium) is built for longer internal runtime, 50 C operation, hot-swap service, and reduced maintenance.
The E91, with sizes up to 40 kVA versus the Li90’s 30. Within 10 to 30 kVA both apply, and the choice then turns on runtime, temperature, and maintenance priorities.
The Li90, roughly 15 to 45 minutes at full load depending on battery configuration versus about 7 to 11 for the E91, and the Li90 scales runtime without external cabinets.
The Li90. Its LFP batteries last longer and are hot-swappable, reducing replacement frequency and service downtime relative to the E91’s VRLA strings.
Related comparisons
Not sure which Xtreme platform fits?
Xtreme Power can help match the Li90 or E91 to your capacity, runtime, temperature, and maintenance requirements.