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SigmasTek  |  SKU: BW-5511

APC BACKUPS BK520 High Performance UPS Replacement Battery

Sale price $26.03 USD Regular price $37.74
Shipping calculated at checkout.

➤ Replacement battery for APC BACKUPS BK520 UPS units

➤ High rate discharge AGM technology with spill-proof design

➤ Maintenance-free for hassle-free use

➤ Brand new, factory fresh with 1 year warranty

➤ U.L. Recognized and CE Certified for safe operation


📦🚀 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 | 12 Ah

Terminal Type

F2

SigmasTek 12V 12Ah Replacement Battery for APC BACKUPS BK520

This SigmasTek replacement battery is engineered specifically for the APC BACKUPS BK520 to restore reliable runtime, high output and consistent protection for your sensitive electronics. Built to meet or exceed the OEM SLA battery specifications, this replacement UPS battery delivers dependable performance and compatibility so your APC BACKUPS BK520 continues to safeguard your devices during power interruptions. Whether you need backup for home office equipment, networking gear, or essential emergency systems, this high-performance UPS battery is designed to deliver the power you expect.

Key Specifications

  • Compatible with: APC BACKUPS BK520
  • Brand: SigmasTek
  • Model: SP12-12HR (replacement equivalent)
  • Voltage: 12 Volts
  • Capacity: 12 Ah
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Design: High Rate Discharge Design
  • Maintenance: Maintenance-Free Design with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

  • Durability and long life: AGM technology and maintenance-free, spill-proof construction mean the battery resists leakage and tolerates normal vibration and handling, giving you a long-lasting battery solution for your APC BACKUPS BK520.
  • High performance: The high rate discharge design supplies exceptional short-term power when your UPS needs it most, making this a high-performance UPS battery ideal for sudden load demands.
  • Reliable emergency power: Use this replacement UPS battery to restore dependable emergency power for routers, modems, small servers, and other critical devices so you remain connected during outages.
  • Maintenance-free convenience: With factory-fresh, sealed AGM construction you avoid fluid maintenance and can install the battery quickly using your existing cables and hardware.
  • Safety and compliance: U.L. recognition and CE certification provide assurance that this battery meets recognized safety standards for consumer and business UPS applications.
  • Versatile applications: Perfect for UPS units, emergency power supply systems, and battery-powered tools that require a dependable 12V 12Ah SLA replacement.

Replace your aging APC BACKUPS BK520 battery with confidence. This SigmasTek 12V 12Ah replacement UPS battery provides the performance, reliability, and safety certifications you need to preserve uptime and protect your equipment. Order now to restore full backup capacity and enjoy a trustworthy, long-lasting battery solution backed by a one-year warranty.


Payment & Security

Payment methods

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