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SigmasTek  |  SKU: BW-5051

ONEAC ON2000I-SN UPS High Performance Compatible Replacement Battery Set

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

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

➤ High rate discharge for optimal UPS and emergency power performance

➤ Valve regulated construction ensures safe, spill-proof operation

➤ Superior vibration resistance protects against shocks and drops

➤ Factory fresh with 1-year warranty and meets OEM specs


📦🚀 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 ONEAC ON2000I-SN UPS

Restore reliable runtime to your ONEAC ON2000I-SN with this brand new replacement UPS battery set. Designed for compatibility, dependable performance, and built-in reliability, these SigmasTek SP12-18HR batteries deliver the high-rate output your ONEAC ON2000I-SN expects. This replacement UPS battery set is ideal when you need a high-performance UPS battery that provides consistent power during outages. Please note: you must reuse all existing cables and hardware from your original configuration to connect these batteries.

Key Specifications

  • Brand: SigmasTek
  • Model: SP12-18HR
  • Voltage: 12 Volts
  • Capacity: 18 AH (Amp-hours)
  • Quantity: 4 batteries (battery set)
  • Terminal Type: Nut & Bolt
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated, Spill Proof
  • Features: Low Self-discharge, High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year

Benefits

These SigmasTek batteries provide a long-lasting battery solution for your ONEAC ON2000I-SN UPS. The high rate discharge design ensures rapid, high-power delivery when your UPS requires short bursts of energy, making this a high-performance UPS battery suited for demanding situations. Valve regulated, spill-proof construction and robust vibration resistance increase durability and safety during transport and operation. Low self-discharge means the batteries retain capacity while in storage so your replacement set is ready when you need it.

Reliability is essential in emergency power systems — these batteries are U.L. recognized and CE certified, factory fresh, and tested to meet or exceed OEM specifications. Typical applications include UPS units, emergency power supply systems, and battery-powered tools. Whether you’re maintaining IT infrastructure, supporting critical network equipment, or preparing backup systems for abrupt outages, this replacement UPS battery set gives you the confidence of consistent runtime and dependable performance.

Orders for in-stock items typically ship within 24 hours. If you need assistance selecting or installing replacement batteries for the ONEAC ON2000I-SN, contact our customer service team at or email us for expert help. Choose a long-lasting battery solution that restores full capability to your UPS quickly and affordably.

Ready to replace the batteries in your ONEAC ON2000I-SN? Buy this high-performance UPS battery set now and get dependable power when it matters most.


Payment & Security

Payment methods

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