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SigmasTek  |  SKU: BW-15766

Union MX-12340 High Performance Replacement Battery

Sale price $91.99 USD Regular price $137.18
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced performance

➤ Maintenance-free and spill-proof design for safety and convenience

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

➤ Brand new and factory fresh to ensure maximum lifespan

➤ 1 year warranty for peace of mind and guaranteed compatibility


📦🚀 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.
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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

Union Battery MX-12340 Battery (Replacement) — Compatible with Union Battery MX-12340

Replace your old Union Battery MX-12340 with a premium replacement battery designed for full compatibility and reliable performance. This high-performance battery is engineered to meet OEM specifications and provide the dependable output needed for critical devices and backup systems.

Key Specifications

  • Model Compatibility: Union Battery MX-12340
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Terminal Type: Nut & Bolt
  • Battery Type: Sealed Lead Acid (SLA)
  • 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

  • Durability: AGM construction and sealed design ensure ruggedness, leak prevention, and resistance to vibration for long-term reliability.
  • Long Life: Maintenance-free SLA chemistry reduces downtime and increases usable service life, making this a long-lasting battery for routine and emergency use.
  • High Performance: With a stable 12V output and 35AH capacity, this battery delivers the steady power necessary for sensitive electronics and power-hungry applications.
  • Safety & Certifications: U.L. Recognized and CE Certified to meet industry safety standards, providing confidence when used in critical systems.
  • Common Uses: Ideal for UPS systems, emergency lighting, security and alarm systems, medical equipment, mobility devices, and many types of portable tools requiring a trustworthy replacement battery.
  • Installation Convenience: Nut & Bolt terminal design provides secure connections and an easy swap-in process for replacing your Union Battery MX-12340.

Ensure uninterrupted performance with this long-lasting battery replacement for the Union Battery MX-12340. Backed by a 1 year warranty and built to OEM-equivalent standards, this high-performance battery is ready to ship. Buy now to restore reliable power to your equipment.


Payment & Security

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