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-5158

Alpha Technologies Nexsys Dual 600 High Performance UPS Replacement Battery Set

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

➤ Replacement battery set with 4 SigmasTek SP12-18HR (12V 18AH) for Alpha Technologies Nexsys Dual 600

➤ High rate discharge supports emergency power and UPS applications

➤ Valve regulated and spill-proof construction for safety and reliability

➤ Low self-discharge preserves battery readiness

➤ Factory fresh and certified 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 Alpha Technologies Nexsys Dual 600 - SigmasTek SP12-18HR (4-Pack)

Keep your Alpha Technologies Nexsys Dual 600 running at peak performance with this full replacement UPS battery set. This 4-pack of SigmasTek SP12-18HR batteries (12 Volts, 18 AH) is engineered for dependable power delivery and high-rate discharge applications that demand short bursts of elevated output. These brand new, factory-fresh batteries are an ideal replacement UPS battery option for maintaining uptime and protecting critical systems. Please note: you must use all existing cables and hardware from your original configuration to hook up the new batteries.

Key Specifications

  • Included Batteries: 4 x SigmasTek SP12-18HR
  • Voltage: 12 Volts
  • Capacity: 18 AH
  • Terminal Type: Nut & Bolt
  • Brand: SigmasTek
  • Compatible With: Alpha Technologies Nexsys Dual 600
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Additional Features: Low Self-discharge; High Vibration Resistance; Superior Performance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

This SigmasTek replacement package offers long-term durability and reliable power under demanding conditions. The high-rate discharge design is especially suited to UPS systems requiring high power for short intervals, delivering the burst capacity needed to protect sensitive electronics. Valve regulated, spill-proof construction minimizes maintenance and risk, while low self-discharge ensures the batteries remain ready after storage. High vibration resistance supports stability in mounted or transportable equipment scenarios, making this a robust high-performance UPS battery choice.

Ideal applications include Uninterruptible Power Supply (UPS) units like the Alpha Technologies Nexsys Dual 600, emergency backup systems, and battery-powered tools used intermittently. Our technical staff individually tests these batteries to confirm they meet or exceed OEM specifications, so you receive a reliable, long-lasting battery that restores runtime and reduces the likelihood of unexpected failures. The product carries U.L. and CE recognition plus a 1 year warranty for added peace of mind.

We typically ship in-stock orders within 24 hours, and our customer service team is available to answer purchase or installation questions. Remember to reuse your original cables and hardware when installing this replacement battery set.

Ready to upgrade your Nexsys Dual 600 with a high-performance UPS battery 4-pack? Purchase now for dependable, long-lasting battery backup and swift shipping.


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.