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SigmasTek  |  SKU: BW-15686

National Battery NB12-40 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 safe, hassle-free use

➤ U.L. Recognized and CE Certified ensuring high safety standards

➤ Brand new and factory fresh for guaranteed reliability

➤ 1 Year warranty for peace of mind and product assurance


📦🚀 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

12 Volts | 40 Ah

Terminal Type

Nut & Bolt

National Battery NB12-40 Replacement Battery — Compatible with National Battery NB12-40

When your National Battery NB12-40 needs replacement, choose this replacement battery that delivers OEM-level compatibility, dependable performance, and long-term reliability. This sealed lead acid (SLA) unit uses AGM technology for improved durability and charge efficiency. It’s a high-performance battery solution designed to meet the needs of demanding standby and cyclic applications.

Key Specifications

  • Compatible Model: National Battery NB12-40
  • 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

This National Battery NB12-40 replacement is built for longevity, offering a long-lasting battery life thanks to AGM construction and quality manufacturing. The maintenance-free, spill-proof design simplifies installation and operation—no electrolyte handling or periodic maintenance is required. Robust construction means it stands up to vibration and frequent use in mobile or industrial environments.

Use this high-performance battery in UPS systems, emergency backup power, alarm and security systems, telecom equipment, and many types of power tools or utility devices. The 12V, 40 Ah capacity provides sufficient runtime for many critical systems, and the nut & bolt terminals create secure connections that are resistant to loosening in high-vibration scenarios.

Safety and quality are confirmed by U.L. recognition and CE certification, and each battery ships brand new and factory fresh. With a 1 year warranty included, you can purchase this replacement battery with confidence, knowing your investment is protected and that you’ll have reliable backup power when it matters most.

Replace your failing NB12-40 now—order this National Battery NB12-40 replacement battery today for a dependable, high-performance, long-lasting battery solution. Click to buy and secure reliable power with fast delivery.



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