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SigmasTek  |  SKU: BW-3145

Alpha Technologies Nexsys 900 UPS High Performance Replacement Battery Set

Sale price $66.60 USD Regular price $96.57
Shipping calculated at checkout.

➤ Four brand new 12V 7.5AH SigmasTek batteries included for the Nexsys 900 UPS

➤ High rate discharge design supports rapid power delivery in critical moments

➤ Valve regulated, spill-proof to prevent leaks and ensure safe operation

➤ Low self-discharge and vibration resistance improve battery longevity

➤ UL recognized and CE certified with a 1-year warranty for quality assurance


📦🚀 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 SigmasTek SP12-7.5HR Battery Set for Alpha Technologies Nexsys 900 UPS

Replace worn cells in your Alpha Technologies Nexsys 900 with this reliable replacement UPS battery set. The pack includes four SigmasTek SP12-7.5HR batteries (12 Volts, 7.5 AH) designed for high rate discharge applications and dependable short-term power delivery. This long-lasting battery solution restores runtime and resilience to your Nexsys 900 so critical systems stay protected during outages.

Key Specifications

  • Included Quantity: 4 batteries (battery set)
  • Model: SigmasTek SP12-7.5HR
  • Voltage: 12 Volts
  • Capacity: 7.5 AH
  • Terminal Type: F2
  • 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
  • Brand: SigmasTek (replacement for Alpha Technologies)

Benefits

As a high-performance UPS battery option for the Nexsys 900, this SigmasTek set offers immediate improvements in reliability and responsiveness. The high rate discharge capability supplies the extra current needed during transient events, while low self-discharge keeps the pack ready after storage or infrequent use. The valve regulated, spill-proof construction simplifies handling and reduces maintenance compared to flooded battery types.

Durability features such as high vibration resistance make this pack suitable for installations where mechanical stresses are present. With U.L. recognition and CE certification, these batteries meet important safety and quality benchmarks. Each battery is brand new, factory fresh, and tested by our experienced technical staff to ensure consistent, long-lasting battery performance that meets or exceeds OEM specifications.

Suitable applications include Uninterruptible Power Supply (UPS) units like the Alpha Technologies Nexsys 900, emergency power systems, and battery-powered tools requiring a compact and dependable power source. Installation requires reuse of all existing cables and hardware from your original configuration; this kit supplies the compatible batteries to restore your Nexsys 900.

Questions about the right replacement UPS battery? Contact our customer service at for expert help. In-stock orders typically ship within 24 hours. Purchase your SigmasTek SP12-7.5HR replacement set for the Alpha Technologies Nexsys 900 today and ensure uninterrupted protection for your equipment.


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