For questions, quotes, or help finding the right battery, feel free to email us at sales@batteryweb.com

New collections added! Learn more

🎉 First Order Special 🎉

First-time shoppers get 5% OFF on batteries & accessories!

WELCOME5
SigmasTek  |  SKU: BW-5141

APC SU1400RMXL UPS Compatible Replacement Battery Set

Sale price $155.20 USD Regular price $225.03
Shipping calculated at checkout.

➤ Includes 4 brand new SigmasTek SP12-18HR batteries (12V 18AH)

➤ High rate discharge design for superior power output

➤ Valve regulated, spill-proof construction for safe operation

➤ Low self-discharge for longer shelf life and reliability

➤ Tested to meet or exceed OEM specs 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.

📸 Send Your Battery Photo / Unsure? Expert Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
POST YOUR IMAGE

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 | 18 Ah

Terminal Type

Nut & Bolt

Replacement Battery Set for APC SU1400RMXL - SigmasTek SP12-18HR (4-pack)

Restore full runtime and reliable protection for your APC SU1400RMXL with this brand new replacement UPS battery set. Designed specifically to match the performance needs of the APC SU1400RMXL, this set delivers dependable power, high-rate discharge capability, and factory-fresh reliability. Whether you need to replace aged cells or upgrade your backup system, this high-performance UPS battery set gives you the confidence of tested components that meet or exceed OEM expectations. Please note that you must reuse all existing cables and hardware from your original configuration to install these batteries.

Key Specifications

  • Compatible UPS Model: APC SU1400RMXL
  • Battery Model: SigmasTek SP12-18HR
  • Quantity: 4 batteries (battery set)
  • Voltage: 12 Volts
  • Capacity: 18 AH (amp-hours)
  • Terminal Type: Nut & Bolt
  • 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

Benefits

This replacement UPS battery set is engineered for durability and consistent performance. The high rate discharge design supports short bursts of higher power output—ideal for demanding UPS loads like the APC SU1400RMXL—while the valve regulated, spill-proof construction minimizes maintenance and increases safety. Low self-discharge helps maintain charge between uses, and high vibration resistance improves resilience in rack-mounted or mobile installations. Certified by U.L. and CE, these cells are manufactured to meet strict safety and quality standards.

Expect a long-lasting battery life when installed and maintained according to your UPS manufacturer’s guidelines. These batteries are factory fresh and individually tested by our technical staff to ensure they match or exceed OEM specifications. Use this replacement UPS battery set for a wide range of applications: Uninterruptible Power Supply (UPS) units, emergency power supply systems, and battery-powered tools that require dependable 12V, 18AH capacity. If your APC SU1400RMXL demands reliable backup runtime, this high-performance UPS battery set is an optimal, cost-effective choice.

Installation reminder: reuse your existing cables and hardware from the original configuration. For assistance choosing the right replacement UPS battery or for installation guidance, contact our customer service at or e-mail our support team.

Buy your replacement batteries for the APC SU1400RMXL UPS unit with confidence today! Secure a long-lasting battery solution and get fast shipping on in-stock items—orders typically ship within 24 hours.


Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.