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SigmasTek  |  SKU: BW-4587

APC SUM48RMXL2U UPS High Performance Replacement Battery Set

Sale price $184.99 USD Regular price $270.27
Shipping calculated at checkout.

➤ Includes 16 SigmasTek SP12-5.5HR batteries (12V, 5.5 AH)

➤ High rate discharge design for short bursts of higher power

➤ Valve regulated, spill-proof construction for safe handling

➤ Low self-discharge and high vibration resistance for reliability

➤ U.L. recognized, CE certified, brand new 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 SUM48RMXL2U

Restore full runtime and dependability to your APC SUM48RMXL2U with this brand new replacement battery set. Engineered for compatibility and consistent operation, the kit contains 16 SigmasTek SP12-5.5HR batteries to deliver the power and reliability your UPS demands. Whether protecting networking equipment, storage arrays, or critical communications hardware, this replacement UPS battery pack provides a professional-grade solution to keep your systems running during outages.

Key Specifications

  • Battery set: 16 SigmasTek SP12-5.5HR batteries
  • Voltage: 12 Volts
  • Capacity: 5.5 AH
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Features: Low Self-discharge
  • Resistance: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Compatibility note: Use all existing cables and hardware from original configuration to connect new batteries

Benefits

This high-performance UPS battery set emphasizes durability, consistent output, and a long service life. The high rate discharge design is tailored for applications where higher power is needed for short periods, making it ideal for UPS systems that support heavy server loads or transient spikes. Valve regulated, spill proof construction enhances safety and minimizes maintenance requirements, while low self-discharge preserves charge when the UPS is idle. The robust vibration resistance ensures reliable operation in rack environments and mobile or transit situations.

Use this replacement UPS battery for Uninterruptible Power Supplies, emergency power systems, and battery-powered tools that require dependable backup power. These SigmasTek cells are tested by experienced technicians to meet or exceed OEM performance, offering you peace of mind and predictable runtime curves for critical equipment. As a long-lasting battery option, this set helps reduce frequency of replacements and overall lifecycle costs while maintaining high availability.

The APC SUM48RMXL2U benefits from this replacement kit’s consistent voltage and capacity characteristics, ensuring the UPS can continue protecting hardware and preventing data loss through power interruptions.

Don't wait—purchase this replacement UPS battery pack for the APC SUM48RMXL2U today and secure reliable, high-performance backup power for your critical systems.


Payment & Security

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