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SigmasTek  |  SKU: BW-5028

APC RBC55 High Performance Compatible Replacement Battery Cartridge

Sale price $293.32 USD Regular price $425.31
Shipping calculated at checkout.

➤ Four 12V 18AH batteries, plug & play ready for APC RBC55 UPS

➤ High rate discharge design for optimal power output

➤ Valve regulated, spill-proof, and maintenance-free

➤ Low self-discharge and high vibration resistance for longevity

➤ U.L. Recognized with 1 Year warranty included


📦🚀 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

24 Volts | 18 Ah

Terminal Type

Special Connector

Compatible Replacement Battery Cartridge for APC RBC55

When your APC RBC55 needs replacement power, choose a compatible, plug-and-play cartridge designed for performance and reliability. This replacement UPS battery cartridge brings together factory-fresh cells and robust protective features to keep your UPS operating when it matters most. It’s a high-performance UPS battery option tailored for dependable backup in small-to-medium UPS systems.

Key Specifications

  • Configuration: Contains four SigmasTek batteries (12 Volts 18 AH each)
  • Brand: SigmasTek
  • Combined listing in product text: SigmasTek 24 Volts 18 Ah (as provided)
  • Connector / Terminal: Special Connector (assembled with wire harnesses, connecting plates and terminal covers)
  • Plug & Play: Batteries pre-assembled and ready to use
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof
  • Features: Low Self-discharge, High Vibration Resistance
  • Safety: U.L. Recognized
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Compatible Model: APC RBC55

Benefits

  • Durability: Built to withstand typical UPS installation stresses with valve-regulated construction and vibration resistance, ensuring long-term mechanical and chemical stability.
  • Long life and reliability: Low self-discharge chemistry and factory testing provide a long-lasting battery that holds charge and is ready for service after storage, representing a dependable long-lasting battery option.
  • High performance: The high rate discharge design supports elevated power output when the UPS must sustain critical loads during outages, qualifying it as a high-performance UPS battery for emergency situations.
  • Installation ease: Pre-assembled with wire harnesses, connecting plates, and terminal covers for plug-and-play replacement that reduces downtime and simplifies maintenance procedures.
  • Safety and compliance: U.L. recognized cells add confidence for deployment in mission-critical environments and commercial installations.
  • Typical applications: Perfect for UPS units using the APC RBC55 cartridge, emergency power supplies, telecom and networking closets, and battery-powered tools that may require short-term high power.

Upgrade your APC RBC55 with this compatible replacement UPS battery cartridge to restore dependable backup power. Orders generally ship within 24 hours — purchase now to ensure continued protection of your critical systems.


Payment & Security

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