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SigmasTek  |  SKU: BW-5303

Alpha Technologies Nexsys 600E UPS High Performance Compatible Replacement Battery Set

Sale price $77.60 USD Regular price $112.53
Shipping calculated at checkout.

➤ Set includes 2 brand new 12V 18AH SigmasTek batteries for Nexsys 600E UPS

➤ High rate discharge capability supports emergency and UPS applications

➤ Valve regulated and spill-proof design offers safe, leak-free operation

➤ Low self-discharge extends battery lifespan when not in use

➤ Tested to meet or exceed OEM specs 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

12 Volts | 18 Ah

Terminal Type

Nut & Bolt

SigmasTek SP12-18HR Replacement Battery Set for Alpha Technologies Nexsys 600E

Specifically tailored to fit the Alpha Technologies Nexsys 600E, this replacement UPS battery set provides reliable, high-rate discharge performance and consistent, factory-fresh reliability. The set includes two SigmasTek SP12-18HR batteries (12 Volts, 18 AH) to restore your Nexsys 600E’s backup capacity. Note: you must reuse all original cables and hardware when connecting these replacement units.

Key Specifications

  • Battery set includes: 2 x SigmasTek SP12-18HR
  • Voltage: 12 Volts
  • Capacity: 18 AH (amp-hours)
  • Battery chemistry/design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Self-discharge: Low Self-discharge
  • Vibration resistance: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Terminal type: Nut & Bolt
  • Brand: SigmasTek (replacement for Alpha Technologies)
  • Compatible with: Alpha Technologies Nexsys 600E Uninterruptible Power Supply (UPS) unit
  • Typical applications: Uninterruptible Power Supply (UPS) Units, Emergency Power Supply, Battery Powered Tools

Benefits

  • Durability: The valve-regulated spill-proof design and enhanced vibration resistance protect internal elements from environmental and mechanical stress.
  • Long life: Low self-discharge properties and brand-new construction help ensure a long-lasting battery that holds charge in standby periods.
  • High performance: Built as a high-performance UPS battery for high-rate discharge scenarios, these cells deliver the short-term power surges needed by the Nexsys 600E during critical events.
  • Tested reliability: Every replacement UPS battery is quality-tested to meet or exceed the OEM expectations for runtime and output.
  • Versatility: Ideal for UPS systems, emergency power backups, and battery-driven tools demanding 12V 18AH capability.
  • Simple swap: Designed to integrate using your existing cables and hardware so technicians can complete replacements quickly and correctly.

Bring your Alpha Technologies Nexsys 600E back to full protection with this reliable, long-lasting battery set. Add to cart now to secure dependable UPS backup power and fast shipment.


Payment & Security

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