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SigmasTek  |  SKU: BW-14475

National C18A Premium Replacement Battery

Sale price $16.99 USD Regular price $24.60
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced performance

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

➤ U.L. Recognized and CE Certified to ensure quality and compliance

➤ Brand new and factory fresh for reliable power every time

➤ Backed by a 1-year warranty for peace of mind


📦🚀 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

6 Volts | 12 Ah

Terminal Type

F1

National Battery C18A Replacement Battery — Compatible with National Battery C18A

Upgrade to a dependable replacement National Battery C18A unit designed for full compatibility with the National Battery C18A model. This high-performance battery uses Absorbent Glass Mat (AGM) technology and a maintenance-free, spill-proof design to deliver consistent, reliable power. Ideal for devices that demand steady performance and safety certifications, the C18A replacement battery offers the long-lasting battery performance you need for critical applications such as UPS systems and emergency power supplies.

Key Specifications

  • Compatible Model: National Battery C18A
  • Replacement Brand: SigmasTek
  • OEM Brand: National Battery
  • Voltage: 6 Volts
  • Capacity: 12 Ah
  • Terminal Type: F1
  • 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

The C18A replacement battery is built to provide durable, consistent energy for a variety of uses. AGM technology offers superior vibration resistance, leak-proof safety, and improved charge acceptance — characteristics that matter in backup power and frequent cycling environments. This maintenance-free battery removes the hassle of periodic water additions and reduces the risk of spills, making it an excellent choice for permanently installed systems and portable equipment alike.

Designed to be a long-lasting battery solution, the C18A replacement is suitable for UPS and emergency power systems, security and alarm equipment, telecom standby units, and small industrial tools. Its 6V 12Ah rating and F1 terminal configuration make it a straightforward, reliable replacement that restores original performance without compromise.

Certified by U.L. and CE, and shipped brand new and factory fresh, this replacement battery meets rigorous safety and quality standards so you can deploy it in sensitive or mission-critical environments with confidence. Backed by a 1 Year Warranty, it provides a balance of value and assurance.

Ready to replace your old battery? Buy the National Battery C18A replacement battery today for a high-performance, long-lasting battery solution that ensures compatibility and peace of mind.



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