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SigmasTek  |  SKU: BW-2551

Liebert Nfinity 12kVA UPS High Performance Replacement Battery Set

Sale price $2,968.99 USD Regular price $4,347.09
Shipping calculated at checkout.

➤ Includes 120 SigmasTek SP12-9HR batteries (12V 9AH) for Liebert Nfinity 12kVA UPS

➤ High rate discharge design for powerful short bursts of energy

➤ Valve regulated, spill-proof for safe, maintenance-free usage

➤ Low self-discharge and vibration resistant for long-term reliability

➤ Brand new batteries with 1 year warranty and certified quality


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

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Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 9 AH

Terminal Type

F2

SigmasTek SP12-9HR Replacement Battery Set for Liebert Nfinity 12kVA UPS

Upgrade the runtime and reliability of your Liebert Nfinity 12kVA UPS with this complete replacement UPS battery set. Engineered for compatibility and performance, this kit includes SigmasTek SP12-9HR batteries designed to deliver stable, high-rate power when your equipment needs it most. Whether you’re maintaining critical infrastructure or refreshing aging battery strings, this high-performance UPS battery solution provides dependable, factory-fresh capacity for uninterrupted operation.

Key Specifications

  • Compatible UPS model: Liebert Nfinity 12kVA
  • Quantity: 120 batteries
  • Battery model: SigmasTek SP12-9HR
  • Voltage: 12 Volts
  • Capacity: 9 AH (Ampere-hours)
  • Terminal: F2
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Features: Low Self-discharge
  • Features: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Note: Use all existing cables and hardware from your original configuration to connect the new batteries

Benefits

This replacement UPS battery set is built for durability and long service life, delivering consistent performance under high-rate discharge conditions. The valve-regulated, spill-proof construction reduces maintenance requirements while providing robust protection against vibration and environmental stresses. As a high-performance UPS battery choice, these SigmasTek SP12-9HR cells are U.L. Recognized and CE Certified, giving you quality assurance for critical power applications.

Because these batteries are designed for high rate discharge, they are ideal for UPS systems like the Liebert Nfinity 12kVA that demand short bursts of higher power output. They also perform exceptionally well in emergency power supply systems and battery-powered tools where reliable, fast energy delivery matters. With low self-discharge characteristics, the cells retain capacity longer in storage and are ready when you need them. Technically tested to meet or exceed OEM specifications, this replacement UPS battery kit ensures your infrastructure remains protected.

We ship in-stock orders quickly — typically within 24 hours — and our knowledgeable customer service team is available to help with installation guidance and compatibility questions. For assistance, call or e-mail our support staff.

Ready to restore full backup capability? Buy this long-lasting battery replacement for your Liebert Nfinity 12kVA today and secure reliable, high-performance UPS power for your critical systems.


Payment & Security

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