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SigmasTek  |  SKU: BW-9945

Bruno Thunder 37 U1 Wheelchair High Capacity Replacement Battery

Sale price $214.25 USD Regular price $280.53
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


📦🚀 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 | 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.


Payment & Security

Payment methods

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