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SigmasTek  |  SKU: BW-4649

APC Smart-UPS X 120V External Battery Pack Rack/Tower (SMX120RMBP2U) UPS High Performance Replacement Battery Set

Sale price $115.99 USD Regular price $168.94
Shipping calculated at checkout.

➤ Includes 10 SigmasTek SP12-5.5HR batteries, 12V 5.5 AH each

➤ High rate discharge for UPS units requiring short bursts of power

➤ Valve regulated and spill-proof for maintenance-free use

➤ Low self-discharge and vibration resistant for extended life

➤ U.L. recognized, CE certified with 1-year warranty


📦🚀 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 | 5.5 Ah

Terminal Type

F2

Replacement Battery Set for APC Smart-UPS X 120V External Battery Pack Rack/Tower (SMX120RMBP2U) - SigmasTek SP12-5.5HR (10-Pack)

For the APC Smart-UPS X 120V External Battery Pack (SMX120RMBP2U), this replacement UPS battery set provides dependable, factory-fresh power to restore and extend runtime. Containing ten SigmasTek SP12-5.5HR batteries, each rated at 12 Volts and 5.5 Ah, this kit is tailored to meet the higher-rate discharge demands of external UPS battery packs. If you require a high-performance UPS battery solution that balances safety, endurance, and OEM-level performance, this set is an excellent match.

Key Specifications

  • Compatible UPS Model: APC Smart-UPS X 120V External Battery Pack Rack/Tower (SMX120RMBP2U)
  • Quantity: 10 SigmasTek SP12-5.5HR batteries
  • Voltage: 12 Volts
  • Capacity: 5.5 Ah
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Performance Features: Low Self-discharge; High Vibration Resistance; Superior Performance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Installation Note: Use all existing cables and hardware from your original configuration to connect the new UPS batteries
  • Typical Applications: Uninterruptible Power Supply (UPS) Units; Emergency Power Supply; Battery Powered Tools

Benefits

These batteries are engineered for tough, real-world UPS applications. The high rate discharge design supplies short-duration, high-current output essential for external battery packs and high-demand loads. Valve regulated and spill-proof construction reduce maintenance and enhance safety within rack and tower environments. Low self-discharge ensures batteries retain charge during storage and deployment cycles, giving you a reliable, long-lasting battery solution when replacing the SMX120RMBP2U pack.

High vibration resistance improves resilience in densely packed data center racks or mobile deployments, while UL and CE recognition confirms compliance with recognized safety standards. The result is a replacement UPS battery pack that supports consistent, predictable performance across emergency power systems, UPS units, and battery-operated tools. Each SigmasTek cell arrives factory fresh and tested to meet or exceed OEM expectations for performance and longevity.

Choose this high-performance UPS battery set to restore runtime, reduce unplanned downtime, and extend the service life of your APC Smart-UPS X external battery pack. It’s a practical, cost-effective way to maintain mission-critical power protection.

Get your replacement UPS battery set for the SMX120RMBP2U today—order now for fast shipping, a 1 year warranty, and a dependable long-lasting battery solution for your critical systems.


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