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Enersys  |  SKU: BW-13257

National Battery NBX12-500 High Performance UPS Replacement 103.09 lb

21% off
Sale price $684.99 USD Regular price $861.99
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Compatible replacement for National Battery NBX12-500 with high-rate discharge design
Delivers 491 Watts per cell at 15-min rate for reliable UPS performance
Low self-discharge rate under 3% per month for up to 10 years standby life
Spill-proof ABS flame retardant case with no-leak, operable in any position
Backed by a 3-year warranty and UL listing for guaranteed quality and safety
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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.

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🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.


Volts & Amps

12 Volts | 145 Ah

Terminal Type

Internal Thread

Replacement National Battery NBX12-500 — Compatible NBX12-500

The replacement National Battery NBX12-500 is a compatible UPS battery engineered for reliable high-rate discharge performance. Designed as a direct replacement for the NBX12-500, this battery offers maintenance-free operation, low self-discharge, and a rugged construction that supports both standby and cycle service. If you need a long-lasting battery to protect critical systems, the NBX12-500 replacement battery delivers dependable power and proven durability.

Key Specifications

  • Model: National Battery NBX12-500 (Replacement)
  • Voltage: 12 Volts
  • Amp-hours: 145 Ah
  • Watts per cell: 491 Watts per cell on 15-min rate at 1.67 Volts
  • Self-discharge rate: Less than 3% per month
  • Expected life in standby use: Up to 10 years
  • Cycle life: Up to 300 cycles at 100% discharge in cycle service
  • Technology: Absorbent Glass Mat Technology (AGM)
  • Case: ABS (UL94 V-0) flame retardant case
  • Construction: Spill Proof Construction; No-leak construction; Can be operated in any position
  • Terminal: Internal Thread
  • Warranty: 3 Year Warranty
  • Certifications: UL Listed
  • Condition: Brand New, Factory Fresh
  • Brand/Supplier text: Enersys

Benefits

This replacement battery is optimized for longevity and reliable high-current response. The AGM construction and the low self-discharge rate help ensure the battery is ready when you are, while the robust ABS UL94 V-0 casing and spill-proof design provide extra safety and durability in enclosed equipment rooms. The NBX12-500’s high-rate capability (491 W per cell at the 15-minute rate) makes it a suitable high-performance battery for UPS and emergency power systems where immediate energy delivery is essential.

Typical applications include uninterruptible power supplies, communication systems, and other mission-critical installations requiring a dependable standby source. It also performs well in cycle applications for controlled discharge and recharge scenarios up to 300 cycles at full discharge. The internal thread terminal supports secure mounting and reliable connections in standard trays and cabinets, and each unit ships brand new and factory tested with a 3-year warranty for added assurance.

Don’t wait until power fails — buy this replacement National Battery NBX12-500 high-performance battery now and secure long-lasting protection for your critical equipment. Order today for fast shipping and reliable backup power.

Technical Specifications

Voltage12 Volts
Amp Hours145 Ah
Terminal TypeInternal Thread
Length (in.)13.3
Width (in.)6.8
Height (in.)10.7
Weight (lb.)103.0

Product Highlights

  • Brand Replacement : National Battery NBX12-500
  • Manufacturer: Enersys
  • Product Type: Heavy Duty Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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