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SigmasTek  |  SKU: BW-13806

National Battery C18D High Performance Compatible Replacement Battery

Sale price $8.99 USD Regular price $12.96
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) Technology for superior performance

➤ Maintenance-Free design with spill-proof construction

➤ U.L. Recognized and CE Certified for safety and reliability

➤ Brand new and factory fresh for long-lasting use

➤ Includes 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 | 7 AH

Terminal Type

F1

Replacement National Battery C18D - Compatible with C18D

This replacement National Battery C18D is engineered to meet or exceed OEM SLA battery specifications and provide dependable, maintenance-free power for emergency systems and standby equipment. If you require a replacement battery that combines safety, high performance, and a long-lasting battery life, the C18D-compatible unit delivers factory-fresh quality and certified reliability to keep critical devices operating without interruption.

Key Specifications

  • Model Compatibility: National Battery C18D
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek
  • Voltage: 6 Volts
  • Capacity/Designation: 7 AHF1
  • Compatibility Note: Meets or exceeds OEM SLA battery specifications

Benefits

  • Rugged and Safe Design: The AGM and spill-proof construction create a sealed, vibration-resistant battery ideal for mounting in cabinets, panels, and compact enclosures found in emergency lighting and alarm systems.
  • Maintenance-Free Operation: As a sealed lead acid unit, this long-lasting battery eliminates the need for periodic electrolyte checks, simplifying upkeep for facility managers and homeowners alike.
  • Consistent High Performance: Built to match or exceed OEM SLA performance, this high-performance battery supports dependable charging and steady discharge profiles—critical for emergency power applications and continuous monitoring systems.
  • Versatile Usage: Suited for emergency lighting, security alarms, fire alarms, consumer electronics, medical equipment, and home & garden applications. Also applicable for UPS backup, emergency power modules, and tool charging in environments where sealed, maintenance-free batteries are preferred.
  • Certified Quality and Support: U.L. recognition and CE certification provide compliance confidence, while the included 1 year warranty and SigmasTek branding back the purchase with support.

Replace your worn C18D battery today to restore reliable emergency power and continuous system protection. Purchase now for competitive pricing, rapid shipping on in-stock items, and the assurance of a one-year warranty on this high-performance replacement battery.


Payment & Security

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