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SigmasTek  |  SKU: BW-9226

Invacare TDX SI-HD High Performance Replacement Battery for Wheelchair

Sale price $156.99 USD Regular price $240.13
Shipping calculated at checkout.

➤ Factory fresh replacement battery for Invacare TDX SI-HD wheelchair

➤ Features Absorbent Glass Mat (AGM) technology for durability

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

➤ Deep cycle design delivers long-lasting power and performance

➤ Compatible with existing cables and hardware, easy to install


📦🚀 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 | 55 AH

Terminal Type

Nut & Bolt

Replacement Invacare TDX SI-HD Battery — Compatible with Invacare TDX SI-HD

Restore reliable power to your Invacare TDX SI-HD with this factory-fresh replacement battery. Designed to be 100% compatible with the Invacare TDX SI-HD unit, the SP12-55 NB (12 V 55 AH) replacement battery delivers consistent performance and dependable runtime. If you need a replacement battery that combines safety, high performance, and a long service life, this option is built to meet the demands of daily mobility and occasional heavy use.

Key Specifications

  • Model Compatibility: Invacare TDX SI-HD
  • Battery Model: SP12-55 NB
  • Voltage: 12 V
  • Capacity: 55 AH
  • Terminal Type: Nut & Bolt
  • Technology: Absorbent Glass Mat (AGM)
  • Design: Designed for Deep Cycle Usage
  • Construction: Valve Regulated Spill Proof
  • Energy Characteristics: 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

Benefits

  • Durability: The sealed AGM design minimizes maintenance and resists leaks, offering durable, safe operation for everyday mobility demands.
  • Long Life: Specifically crafted for deep cycle use, this long-lasting battery endures repeated charging and discharging while preserving usable capacity.
  • High Performance: Engineered with a high power/volume ratio, this high-performance battery supplies the energy density needed for consistent acceleration, control response, and accessory operation.
  • Quality & Safety: U.L. recognized and CE certified, ensuring adherence to recognized safety and quality standards for mobility batteries.
  • Versatile Applications: Primarily intended for electric wheelchairs, power chairs, mobility chairs, and mobility scooters. It is also an excellent option for compatible UPS backup, emergency power needs, and certain portable tool applications that accept a sealed 12 V, 55 AH battery.
  • Hassle-Free Installation: Install easily using your existing cables and nut & bolt terminals — no special hardware required.
  • New & Guaranteed: Brand new, factory fresh battery with a 1 year warranty and a performance guarantee for confidence with every purchase.

Don’t compromise on power or reliability. Buy this replacement Invacare TDX SI-HD battery now and get a long-lasting battery solution that keeps your mobility device performing at its best. Order today to secure fast shipping and dependable service.


Payment & Security

Payment methods

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  • Discover
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  • Visa

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