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

🎉 First Order Special 🎉

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

WELCOME5
SigmasTek  |  SKU: BW-15687

National Battery C40A High Performance Replacement Battery

Sale price $113.99 USD Regular price $170.58
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced durability

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

➤ U.L. Recognized and CE Certified ensuring safety and quality

➤ Brand new and factory fresh for reliable performance

➤ 1 year warranty for peace of mind and protection


📦🚀 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 | 40 Ah

Terminal Type

Nut & Bolt

National Battery C40A Replacement Battery — Compatible with National Battery C40A

Restore reliable power to your National Battery C40A-equipped system with this replacement battery designed for direct compatibility and consistent performance. As a sealed lead acid (SLA) battery using AGM technology, this product offers a maintenance-free, spill-proof power source that is ideal for both standby and cyclic uses. Count on this long-lasting battery to deliver steady output when you need it most.

Key Specifications

  • Compatible Model: National Battery C40A
  • Replacement Brand: SigmasTek
  • Chemistry: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 40 Ah
  • Terminal Type: Nut & Bolt
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year

Benefits

The National Battery C40A replacement delivers durability and dependable performance through AGM construction that resists vibration and improves cycle life. As a maintenance-free design it removes the need for routine upkeep, which is especially valuable in installations where access is limited or continuous operation is critical. The spill-proof construction also enhances safety during handling and installation.

This high-performance battery suits a wide range of applications including UPS and emergency backup, security and alarm systems, telecom cabinets, and portable power tools. With a 12V, 40 Ah rating, it provides ample capacity for extended backup and steady discharge characteristics, helping connected equipment remain operational through outages and load events. Nut & bolt terminals make for robust, secure connections appropriate for industrial and mobile setups.

Safety certifications (U.L. Recognized and CE Certified) and the brand new, factory fresh condition ensure consistency and compliance with industry standards. Plus, a 1 year warranty gives you extra assurance in the quality and longevity of this replacement battery.

Ready to upgrade to a reliable, long-lasting battery? Purchase this National Battery C40A replacement battery today to secure a high-performance battery solution with reliable backup power. Click to buy now for fast delivery and competitive pricing.



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.