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SigmasTek  |  SKU: BW-16216

Alexander GB12240 High Performance Replacement Battery

Sale price $116.23 USD Regular price $133.48
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced performance

➤ Maintenance-free and spill-proof design for safe, hassle-free use

➤ U.L. Recognized and CE Certified for reliable quality assurance

➤ 100% compatible replacement for Alexander GB12240 model

➤ Comes with a 1-year warranty and best price guarantee


📦🚀 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 | 26 Ah

Terminal Type

Nut & Bolt

Alexander GB12240 Replacement Battery — Compatible with GB12240

The Alexander GB12240 replacement battery from SigmasTek is engineered for dependable compatibility, steady output, and reliable service life. This replacement battery meets or exceeds OEM SLA specifications and provides a practical, maintenance-free option for anyone needing a high-performance battery that installs easily and performs reliably. Designed for a wide range of standby and portable applications, this long-lasting battery is an excellent drop-in replacement for the GB12240 model.

Key Specifications

  • Compatible Model: Alexander GB12240
  • Brand (Replacement): SigmasTek
  • Voltage: 12 Volts
  • Capacity: 26 Ah
  • Terminal Type: Nut & Bolt
  • Technology: Absorbent Glass Mat (AGM)
  • Design: Maintenance-Free, Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

With AGM technology and a maintenance-free, spill-proof design, this replacement battery delivers dependable performance and reduced upkeep compared to conventional flooded batteries. The secure nut-and-bolt terminals support stable connections that resist loosening and corrosion, which is especially valuable in UPS units, emergency power systems, alarm equipment, and other mission-critical applications.

This high-performance battery is crafted to provide consistent output and a long service life, making it a trustworthy component for backup power and portable applications alike. UL recognition and CE certification confirm adherence to recognized safety and performance standards, while the brand-new, factory-fresh condition ensures maximum capacity and reliability from the start.

Choosing the SigmasTek GB12240 replacement reduces downtime and simplifies maintenance, offering an effective way to restore or upgrade power systems quickly. Backed by a 1 Year Warranty, it provides added confidence for both residential and commercial deployments where dependable, long-lasting battery power is essential.

Don’t wait until a failure interrupts operations—purchase the SigmasTek replacement for the Alexander GB12240 today and secure a reliable, long-lasting battery for your critical systems.


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