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SigmasTek  |  SKU: BW-2049

Belkin BU304000 UPS Compatible Replacement Battery Set

Sale price $14.99 USD Regular price $20.55
Shipping calculated at checkout.

➤ Includes 2 SigmasTek SP6-4.5 batteries (6 Volts 4.5 AH) for Belkin BU304000

➤ High rate discharge for short bursts of high power output

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

➤ Low self-discharge rate and strong vibration resistance

➤ Factory fresh with U.L. recognition, CE certification, and 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

6 Volts | 4.5 AH

Terminal Type

F1

Replacement Battery Set for Belkin BU304000 — SigmasTek SP6-4.5 (Compatible with Belkin BU304000)

Replace worn batteries in your Belkin BU304000 with a dependable, high-performance replacement UPS battery set that restores backup power and system reliability. This pair of SigmasTek SP6-4.5 batteries is specially designed to deliver the performance needed for UPS operation, offering a long-lasting battery solution for your Belkin unit. Count on consistent output, safe construction, and factory-fresh condition to protect your critical equipment.

Key Specifications

  • Included: 2 x SigmasTek SP6-4.5 batteries
  • Voltage: 6 Volts
  • Capacity: 4.5 AH (amp-hours)
  • Battery Model: SP6-4.5
  • Terminal Type: F1
  • Number of Batteries: 2 (battery set)
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Self-discharge: Low Self-discharge
  • Durability: 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 your original configuration to connect the new UPS batteries
  • Typical processing: In-stock items typically ship within 24 hours

Benefits

These SP6-4.5 batteries are engineered for high-rate discharge performance, making them an excellent high-performance UPS battery option for the Belkin BU304000. The valve regulated, spill proof design means safer operation and no need for routine electrolyte maintenance, while low self-discharge preserves stored charge to extend shelf life and readiness.

Built to resist vibration and manufactured factory-fresh, these batteries provide dependable service life and predictable runtime under the load demands of UPS systems. The U.L. recognition and CE certification confirm that these batteries meet industry standards for safety and quality. Whether protecting home office equipment, networking gear, or emergency systems, this replacement UPS battery set provides reliable results.

Recommended applications include Uninterruptible Power Supply units, Emergency Power Supply backups, and Battery Powered Tools. Our technical team tests each replacement set to ensure it meets or exceeds OEM expectations for the Belkin BU304000 so you can rely on a long-lasting battery that restores the functionality of your UPS.

Ready to upgrade your Belkin BU304000? Purchase this SigmasTek SP6-4.5 replacement battery set now for fast shipping and trusted, long-lasting battery performance.


Payment & Security

Payment methods

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