For questions, quotes, or help finding the right battery, feel free to email us at sales@batteryweb.com

New collections added! Learn more

🎉 First Order Special 🎉

First-time shoppers get 5% OFF on batteries & accessories!

WELCOME5
SigmasTek  |  SKU: BW-8356

Invacare 51 High Performance Replacement Battery By SigmasTek

Sale price $107.13 USD Regular price $140.27
Shipping calculated at checkout.

➤ Powerful 35Ah capacity for extended wheelchair use

➤ Consistent 12-volt output ensures smooth performance

➤ High-quality SigmasTek brand guarantees durability

➤ NB terminal design allows for easy, secure installation

➤ Ideal replacement to keep your Invacare 51 wheelchair reliable


📦🚀 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.

📸 Send Your Battery Photo / Unsure? Expert Help

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.
POST YOUR IMAGE

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

SigmasTek 12V 35Ah Replacement Battery — Compatible with Invacare 51 Wheelchair

Maximize the performance of your Invacare 51 Wheelchair with the SigmasTek 12 volt 35 amp hour replacement battery. Built for dependable everyday use, this battery combines substantial capacity, reliable output, and ease of installation via NB (Nut & Bolt) terminals. As a trusted SigmasTek product, it gives Invacare 51 users a long-lasting battery option to support mobility and reduce downtime.

Key Specifications

  • Compatible Model: Invacare 51 Wheelchair
  • Voltage: 12 Volts
  • Capacity: 35 Ah (amp-hours)
  • Terminal Type: NB (Nut & Bolt)
  • Brand: SigmasTek

Benefits

This SigmasTek replacement battery is engineered to be a high-performance battery that supports extended mobility and consistent operation. The 35Ah capacity delivers longer run times between charges, which is especially helpful for daily commutes, errands, and extended outings. The stable voltage output ensures smooth acceleration and controlled operation of your Invacare 51, while the NB terminals provide secure, low-resistance connections for safe and efficient power transfer.

Durability and longevity are key advantages of choosing a SigmasTek battery. Designed to minimize capacity loss over repeated charging cycles, this long-lasting battery helps reduce maintenance frequency and replacement costs over time. It’s an ideal replacement battery for users who require reliable power and fewer interruptions.

In addition to wheelchair applications, the 12V 35Ah SigmasTek battery is useful for a variety of secondary roles including small UPS backup systems, emergency power for lighting, and compatible portable tools. Its combination of capacity, brand quality, and dependable connectors makes it a flexible option for both mobility and auxiliary power needs.

Ready to keep your Invacare 51 Wheelchair performing at its best? Order the SigmasTek 12V 35Ah replacement battery now and experience the benefits of a high-performance, long-lasting battery that you can trust.


Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.