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SigmasTek  |  SKU: BW-15998

National C03A High-Performance Replacement Battery

Sale price $14.99 USD Regular price $28.46
Shipping calculated at checkout.

➤ Meets or exceeds OEM National Battery C03A specifications

➤ Absorbent Glass Mat (AGM) technology for reliable performance

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

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

➤ Includes 1-year warranty and guaranteed 100% 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.

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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 | 3.5 Ah

Terminal Type

F1

National Battery C03A Replacement - Compatible with National Battery C03A

Upgrade your device with a replacement battery designed for dependable performance and complete compatibility. This National Battery C03A replacement is engineered to meet or exceed the OEM specifications, delivering reliable rechargeability, consistent power output, and the peace of mind that comes with factory-fresh components. Whether you need emergency standby power or a dependable cell for daily use, this high-performance battery offers a maintenance-free, spill-proof design and proven safety certifications to keep your equipment running smoothly.

Key Specifications

  • Model Compatibility: National Battery C03A
  • Battery Type: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 3.5 Ah
  • Terminal Type: F1
  • Brand: SigmasTek
  • Design: Maintenance-Free, Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

This National Battery C03A replacement battery delivers long-lasting battery life through durable AGM construction and a maintenance-free sealed design. Its absorbent glass mat (AGM) technology improves vibrational resistance and reduces internal leakage risk, making it a rugged choice for both stationary and portable applications. As a high-performance battery, it provides steady voltage and reliable charge acceptance, ideal for devices that require consistent, repeatable power cycles.

The sealed, spill-proof construction means worry-free installation and safe operation in confined equipment housings. With U.L. recognition and CE certification, this replacement battery complies with key safety standards, helping protect sensitive electronics and connected systems. Typical applications include UPS systems, emergency lighting, alarm panels, medical devices, security systems, and portable tools — anywhere a dependable 12 Volt, 3.5 Ah SLA battery is required.

Choosing this National Battery C03A replacement ensures you receive a brand-new unit from SigmasTek that is built to perform. If you are searching for a replacement battery that balances reliability, performance, and value, this option delivers a long-lasting battery solution that stands up to daily demands and emergency use alike.

Ready to replace your C03A with a high-performance battery that you can trust? Add this National Battery C03A replacement to your cart now and secure reliable power backed by a 1 Year Warranty.



Payment & Security

Payment methods

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