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SigmasTek  |  SKU: BW-6291

ADT Security B4520638 High Performance Compatible Replacement Battery for Alarm Systems

Sale price $129.37 USD Regular price $156.20
Shipping calculated at checkout.

➤ Meets or exceeds original OEM specifications for reliable performance

➤ Valve regulated, spill-proof design for safe indoor use

➤ U.L. recognized and CE certified for quality assurance

➤ Rugged plastic case ensures durability and long-lasting protection

➤ Includes 1 brand new, factory fresh 12V 40AH battery with 1-year warranty


📦🚀 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

ADT Security B4520638 Replacement Battery - SP12-40 NB (Compatible with B4520638)

Ensure uninterrupted protection for your ADT Security B4520638 system with this premium replacement battery. The SP12-40 NB (12 V 40 AH) is engineered to meet or exceed OEM specifications, delivering dependable reserve power, consistent recharging performance, and rugged reliability for residential and commercial installations. If you need a high-performance battery that keeps your security system ready when it matters most, this B4520638-compatible solution is an excellent choice.

Key Specifications

  • Compatible Model: ADT Security B4520638
  • Included Battery: 1 × SP12-40 NB
  • Voltage: 12 Volts
  • Capacity: 40 AH
  • Terminal Type: Nut & Bolt
  • Construction: Valve Regulated Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Case: Rugged Plastic Case and Cover
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek

Benefits

This replacement battery delivers robust performance and extended service life for demanding standby and cyclic applications. The SP12-40 NB’s valve regulated, spill-proof design and reinforced case provide superior durability and safe operation in alarm panels, power supply cabinets, and equipment racks. As a high-performance battery rated for 40 AH, it supplies ample reserve capacity for prolonged outage periods and frequent load demands, translating to a long-lasting battery solution that reduces maintenance cycles.

Ideal uses include home alarm systems, commercial burglar and security systems, access control, and larger power supply applications where extended runtime is required. The same reliability also makes it suitable for UPS systems, emergency power setups, and auxiliary power for field tools and equipment. The nut & bolt terminal configuration ensures secure connections in installations where vibration or movement could otherwise loosen push-on terminals.

Certified to U.L. and CE standards and sold factory fresh with a 1 year warranty, this ADT-compatible battery is backed by quality assurance and customer support. It’s manufactured to match OEM performance while offering a cost-effective alternative to original branded units.

Protect your ADT Security B4520638 system with a trusted, high-performance replacement battery. Add the SP12-40 NB to your cart now and enjoy reliable backup power when you need it most.


Payment & Security

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