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SigmasTek  |  SKU: BW-10761

Theradyne Investigator-Power T-Bird High Performance Wheelchair Replacement Battery

Sale price $214.25 USD Regular price $280.53
Shipping calculated at checkout.

➤ Factory fresh replacement batteries for Theradyne Investigator-Power T-Bird wheelchairs

➤ Uses Absorbent Glass Mat (AGM) technology for deep cycle performance

➤ Valve regulated, spill-proof design ensures safety and reliability

➤ High energy density delivers longer power and improved battery life

➤ U.L. Recognized, CE Certified, with 1-year warranty for guaranteed quality


📦🚀 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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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.
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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

Theradyne Investigator-Power T-Bird Batteries - SP12-35 NB (Compatible with Theradyne Investigator-Power T-Bird)

These brand new replacement batteries are designed to be fully compatible with the Theradyne Investigator-Power T-Bird and deliver the robust performance required by power chairs and mobility systems. Sold as a matched pair to meet the T-Bird’s requirement, these AGM deep-cycle batteries provide reliable energy density, strong starting power, and proven durability. If you need a dependable, long-lasting battery solution for your mobility device, these high-performance batteries are an excellent choice.

Key Specifications

  • Compatible Model: Theradyne Investigator-Power T-Bird
  • Battery Part: SP12-35 NB
  • Quantity Required: 2 batteries
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Terminal Type: Nut & Bolt
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Designed For Deep Cycle Usage
  • Valve Regulated Spill Proof Construction
  • Power/Volume Ratio Yielding Unrivaled Energy Density
  • U.L. Recognized and CE Certified
  • Performance Guaranteed
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek
  • Installation Note: You must use all existing cables and hardware from your original configuration to connect the new wheelchair batteries

Benefits

  • Durability: The AGM design and valve-regulated construction resist spills and vibration, providing a rugged, maintenance-free power source ideal for mobility use and frequent transport.
  • Long Life: Built for deep cycle performance, these long-lasting batteries support repeated charge cycles and sustained use, reducing replacement frequency and total ownership cost.
  • High Performance: High energy density and superior starting power give reliable acceleration, grade-climbing ability, and consistent range for power chairs and mobility scooters.
  • Certified Safety: U.L. Recognition and CE Certification ensure compliance with recognized safety standards for medical and mobility systems.
  • Versatile Applications: Optimized for Electric Wheelchairs, Power Chairs, Mobility Chairs, and Mobility Scooters, these batteries are also useful in UPS backup roles, emergency power situations, and as power sources for portable tools and equipment that accept 12V 35AH modules.
  • Simple Installation: Supplied as the correct pair for Theradyne Investigator-Power T-Bird, they install using your device’s existing cables and hardware for an efficient replacement process.

Replace both batteries in your Theradyne Investigator-Power T-Bird with this reliable SP12-35 NB pair today. Purchase now to get a high-performance, long-lasting battery solution backed by a one-year warranty and prompt shipping—restore full power and confidence to your mobility device.


Payment & Security

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