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SigmasTek  |  SKU: BW-4269

APC BACKUPS BK420SI UPS High Performance Replacement Battery

Sale price $16.99 USD Regular price $24.15
Shipping calculated at checkout.

➤ Advanced AGM technology for enhanced battery efficiency

➤ High rate discharge supports UPS emergency backup

➤ Maintenance-free, spill-proof design for convenience

➤ U.L. recognized and CE certified for quality assurance

➤ Fits APC BACKUPS BK420SI, backed by 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 | 7.5 Ah

Terminal Type

F2

Replacement APC BACKUPS BK420SI Battery — Compatible with APC BACKUPS BK420SI

Upgrade the backup capability of your APC BACKUPS BK420SI with this dependable replacement UPS battery. Designed to meet or exceed OEM SLA battery specifications, it combines AGM technology with a high-rate discharge profile to deliver consistent runtime and dependable protection. This long-lasting battery is ideal for maintaining uptime for critical devices during power interruptions.

Key Specifications

  • Compatible Model: APC BACKUPS BK420SI
  • Battery Type: Absorbent Glass Mat (AGM) Technology
  • Voltage: 12 Volts
  • Capacity: 7.5 Ah
  • Terminal Type: F2
  • Design Feature: 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
  • Applications: Emergency Power Supply, Battery Powered Tools
  • Brand: SigmasTek

Benefits

  • Rugged Durability: Sealed AGM cells and spill-proof design provide a dependable, low-maintenance replacement UPS battery suited for home and light commercial UPS units.
  • Reliable Long Life: High-rate discharge capability supports repeated power events and ensures dependable performance over the battery’s service life.
  • Superior Performance: Engineered to meet OEM specs, this battery supplies stable voltage for safe shutdown and protection of sensitive electronics connected to your APC BACKUPS BK420SI.
  • Maintenance-Free Operation: The sealed, factory-fresh unit requires no routine maintenance, simplifying replacement and reducing downtime.
  • Wide Application: Well-suited for UPS backup, emergency power setups, and battery-powered tools that rely on a consistent source of power.
  • Safety Certifications: U.L. recognition and CE certification provide reassurance for compliant installations.

Don’t risk downtime—replace your APC BACKUPS BK420SI battery today with this high-performance, long-lasting battery. Order now to restore reliable backup power and enjoy the protection of a 1 year warranty.


Payment & Security

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