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SigmasTek  |  SKU: BW-9945

Bruno Thunder 37 U1 Wheelchair High Capacity Replacement Battery 49.45 lb

16% off
New arrival
Sale price $245.99 USD Regular price $292.99
Shipping calculated at checkout.
Factory fresh replacement batteries for Bruno Thunder 37 U1 wheelchair
100% compatible with Bruno Thunder 37 U1 unit, ensuring easy installation
Uses Absorbent Glass Mat (AGM) technology for deep cycle performance
Valve regulated, spill-proof design for safe and reliable use
Comes with a 1-year warranty and guaranteed high performance
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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 | 35 AH

Terminal Type

Nut & Bolt

Replacement Bruno Thunder 37 U1 Battery - Compatible with Bruno Thunder 37 U1

Restore full runtime and reliability to your Bruno Thunder 37 U1 mobility unit with these brand new replacement batteries. Designed specifically for the Bruno Thunder 37 U1, this high-performance replacement battery solution offers deep-cycle capability, factory-fresh construction, and proven compatibility. Your Bruno Thunder 37 U1 requires two SP12-35 NB batteries (12 V 35 AH), and these units deliver the dependable power and long-term reliability you expect while allowing you to reuse your existing cables and hardware for an easy swap.

Key Specifications

  • Model: SP12-35 NB
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Chemistry / Technology: Absorbent Glass Mat (AGM) Technology
  • Design: Designed For Deep Cycle Usage
  • Construction: Valve Regulated Spill Proof Construction (VRLA)
  • Energy Density: Power/Volume Ratio Yielding Unrivaled Energy Density
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek
  • Terminal Type: Nut & Bolt
  • Configuration Note: Bruno Thunder 37 U1 requires 2 batteries — use all original cables and hardware to connect replacements

Benefits

  • Durability: AGM construction and valve-regulated, spill-proof design offer resistance to vibration and accidental tipping for worry-free daily use.
  • Long Life: Engineered for deep cycle use to provide a long-lasting battery experience and predictable recharge cycles for mobility equipment.
  • High Performance: Exceptional energy density and optimized power-to-volume ratio produce extended runtime without sacrificing compact form factor.
  • Safety & Certification: U.L. and CE certifications reinforce safety and performance expectations for mobility and medical accessory applications.
  • Installation Ease: 100% compatibility with Bruno Thunder 37 U1 simplifies replacement — retain your original cables and hardware to connect these batteries quickly.
  • Wide Applications: Ideal as a replacement battery for electric wheelchairs, power chairs, mobility chairs, and mobility scooters. Also well-suited to auxiliary power, small UPS systems, or portable backup scenarios requiring a robust 12 V 35 AH deep-cycle battery.
  • Warranty & Support: Comes factory fresh with a 1 year warranty and performance guarantee from SigmasTek.

Don’t let depleted batteries slow you down — purchase these high-performance, long-lasting replacement batteries for your Bruno Thunder 37 U1 today. Order now for fast shipping and dependable mobility power.

Technical Specifications

Voltage12 Volts
Amp Hours35 AH
Terminal TypeNut & Bolt
Length (in.)7.72
Width (in.)5.14
Height (in.)6.22
Weight (lb.)49.4

Product Highlights

  • Brand Replacement : Bruno Thunder 37
  • Manufacturer: SigmasTek
  • Product Type: Medical Equipment Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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