Welcome to our store. Your trusted source for batteries and power solutions. Learn more

For support or quotes: sales@batteryweb.com
WELCOME5
SigmasTek  |  SKU: BW-5047

ONEAC ON900X UPS High Performance Replacement Battery Set 50.64 lb

14% off
New arrival
$216.99 USD $251.99
Shipping calculated at checkout.
Includes 4 brand new SigmasTek SP12-18HR batteries (12V 18AH)
High rate discharge design for short bursts of high power output
Valve regulated, spill-proof construction ensures safe operation
Low self-discharge extends shelf life and reliable readiness
U.L. recognized, CE certified with 1-year warranty for peace of mind
In stock

— Ready to ship immediately
Free shipping
Visa Mastercard American Express PayPal Apple Pay Google Pay Shop Pay Discover Klarna Afterpay Stripe
✦

Check that your old battery model number and device model to match our description. This makes sure they work together.

✦

We ship your order same day if you buy it before 4 PM EST.

Let customers speak for us

from 22 reviews

WORKS GREAT!

Anonymous

Fast shipping and fair pricing. I will look to you for future battery purchases.

Anonymous

It's hard to rate a battery until some time has passed and it either continues functioning as it should of "gives up the ghost." It was not a straight bolt in application. The positive terminal was different than the stock battery and the positive lead from the motorcycle had to be bent in order to attach it to the battery. Otherwise, if the battery gives long service I have no complaints.

Anonymous

Shopping with you is a bit difficult; I had to type in a few words differently before I could find the battery's I was looking for.

Laura J

Excellent Product, timely delivery, love the extra battery life. Would recommend. rk

Robin Keister

Very easy to buy, high confidence that it was legit company. Reviews were good. Price, in the ball park. We'll see when I get battery.

Rob

Thank you for supplying the battery that I wanted. It arrived today in good order. Its specifications are as advertised and after charging, performs as expected.
Thank you for your professional approach to the payment method.
Regards Roy VK4ZQ.

Roy O'Malley

It worked

Mel Light

Finally found a battery that is similar in function to original equipment.

Anonymous

I'm writing this review to express my deep gratitude and appreciation for the quality of services provided to me by the BatteryWeb service team. I visited BatteryWeb to purchase a replacement battery for my Remington R9 razor. The staff was very responsive and I was really impressed with their willingness to help me and make the purchasing process as quick as possible. In particular I greatly appreciate the work of staff member Shane who was friendly and helpful.
In conclusion, I believe that BatteryWeb has excellent service staff who make their customers feel honored and valued.
I wish you all the best.
Sincerely,
Michael

Michael Talianker

this battery was just what I needed.

Robert Jones

Product is exactly as described and arrived quickly

Robert Jones

Great deal for the money.

Linda M.

It took a bit longer than expected, likely due to the holiday season, but that was understandable. So far, the battery seems to be working well!

Linda M.

Easy to purchase

Alberto J.

Send Your Battery Photo

Expert Technician 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 BATTERY IMAGE
Product & Solutions Expert

Product & Solutions Expert

✉ sales@batteryweb.com

🔹 10+ Years Battery Experience 🔹 Fast & Accurate Identification

Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

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.

Category

UPS Batteries

Brand Replacement

SigmasTek

Volts & Amps

12 Volts | 18 Ah

Terminal Type

Nut & Bolt

Replacement Battery Set for ONEAC ON900X (4 SigmasTek SP12-18HR)

Restore dependable backup power to your ONEAC ON900X with this factory-fresh replacement battery set crafted for compatibility, reliability, and sustained performance. This set contains four SigmasTek SP12-18HR batteries (12 Volts, 18 AH) designed to meet the demands of high-rate discharge scenarios. If you need a replacement UPS battery that returns your unit to reliable operation, this high-performance UPS battery kit is an ideal choice.

Key Specifications

  • Included Batteries: 4 x SigmasTek SP12-18HR
  • Voltage: 12 Volts (each)
  • Capacity: 18 AH (amp-hours) (each)
  • Terminal Type: Nut & Bolt
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated, Spill Proof
  • 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
  • Installation Note: Requires reuse of existing cables and hardware from original configuration
  • Brand: SigmasTek
  • Compatible UPS Model: ONEAC ON900X

Benefits

  • Rugged reliability — The valve regulated, spill-proof construction and high vibration resistance provide dependable service in rack, floor, or field environments, ensuring your UPS is protected.
  • Extended usability — Low self-discharge preserves stored capacity until installation, offering a long-lasting battery solution that reduces the need for frequent replacements.
  • Peak performance for critical loads — With a high rate discharge design, these cells supply the quick, high-power output required during brief but demanding events, making this a true high-performance UPS battery.
  • Multi-purpose — Perfect for Uninterruptible Power Supply (UPS) units, emergency power systems, and battery-powered tools that require reliable burst power.
  • Tested to spec — Our technical team verifies each replacement UPS battery to meet or exceed OEM standards so your ONEAC ON900X performs as expected.

Don’t wait until runtime degrades—purchase this replacement UPS battery set for the ONEAC ON900X today. Orders for in-stock items typically ship quickly and are backed by a 1 year warranty. Click to buy now and restore dependable backup power.

Technical Specifications

Voltage12 Volts
Amp Hours18 Ah
Terminal TypeNut & Bolt
Length (in.)7.13
Width (in.)3.0
Height (in.)6.59
Weight (lb.)50.6

Product Highlights

  • Brand Replacement : ONEAC ON900X
  • Manufacturer: SigmasTek
  • Product Type: UPS Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Bancontact
  • Bizum
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • MB WAY
  • 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.

Our Collections