National Battery C18B High Performance Replacement Battery
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🔹 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 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
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
⚠️ 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 | 8.5 Ah
Terminal Type
F1
National Battery C18B Replacement Battery — Compatible with National Battery C18B
Designed to replace the National Battery C18B, this replacement battery delivers dependable compatibility, steady output, and maintenance-free convenience. The SigmasTek 6 Volt 8.5 Ah SLA battery leverages Absorbent Glass Mat (AGM) technology to provide a safe, spill-proof, factory-fresh power source that meets or exceeds OEM specifications. If you want a long-lasting battery that supports critical systems with consistent performance, the C18B replacement is an excellent high-performance battery option.
Key Specifications
- Compatible Model: National Battery C18B
- Replacement Brand: SigmasTek
- Voltage: 6 Volts
- Capacity: 8.5 Ah
- Terminal Type: F1
- Battery Type: Rechargeable Sealed Lead Acid (SLA)
- Technology: Absorbent Glass Mat (AGM) Technology
- Design: Maintenance-Free with Spill Proof Construction
- Safety & Compliance: U.L. Recognized and CE Certified
- Condition: Brand New, Factory Fresh
- Warranty: 1 Year Warranty
Benefits
The National Battery C18B replacement is built for long service life and reduced maintenance. AGM construction improves internal recombination of gases and minimizes electrolyte loss, enabling a sealed, spill-proof design ideal for sensitive installations. As a high-performance battery, it supports reliable start-up currents and consistent float voltage—key for uninterrupted power supplies and emergency systems. The maintenance-free characteristic simplifies ownership and reduces downtime associated with routine battery care.
Typical uses include UPS units, emergency lighting and backup power, security and fire alarm panels, medical equipment backups, and small portable devices that require a dependable 6V source. The 8.5 Ah capacity provides a practical balance of compact size and useful run-time for many standby and cyclic applications. Certified by U.L. and CE, this replacement battery meets recognized safety and quality standards for both consumer and professional use.
If you need a replacement battery that delivers reliable performance and a long-lasting battery life without the premium OEM price, the SigmasTek National Battery C18B replacement is an effective solution backed by a 1 year warranty.
Ready to secure reliable backup power? Add the National Battery C18B replacement battery to your cart and enjoy a high-performance, long-lasting battery you can trust.
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