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SigmasTek  |  SKU: BW-15739

BS B12-40 High Performance Replacement Battery

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

➤ Compatible replacement for BS Battery B12-40 with 100% OEM specification match

➤ Brand new, factory fresh sealed lead acid battery for reliable performance

➤ UL listed for safety and quality assurance

➤ Includes minimum one-year warranty for peace of mind

➤ Fast shipping within 24 hours with stock readily available


📦🚀 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

BS Battery B12-40 Replacement Battery — Compatible with BS Battery B12-40

The BS Battery B12-40 replacement battery offers dependable compatibility, strong performance, and reliable construction for your BS Battery B12-40 device. Supplied brand new and factory fresh, this rechargeable Sealed Lead Acid (SLA) replacement battery meets or exceeds OEM SLA battery specifications and is intended to provide the consistent, long-lasting battery power required for demanding applications.

Key Specifications

  • Model: BS Battery B12-40 (Replacement)
  • Compatible Model: BS Battery B12-40
  • Chemistry: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: UL Listed
  • Condition: Brand New, Factory Fresh
  • Warranty: Minimum of 1 Year Warranty
  • Supplier/Brand: SigmasTek (as listed)
  • Voltage: 12 Volts
  • Capacity: 40 Ah
  • Terminal Type: Nut & Bolt

Benefits

This replacement battery is crafted to be durable and maintenance-free, helping you avoid the routine service requirements of older battery types. The AGM construction improves vibration resistance and internal gas recombination, contributing to a longer service life and fewer replacements over time. With UL listing, the pack adheres to recognized safety standards for peace of mind in both residential and commercial settings.

As a high-performance battery option, the BS Battery B12-40 delivers consistent output and dependable recharge cycles—making it suitable for continuous duty or standby applications. Its maintenance-free, spill-proof design simplifies handling and installation, and contributes to a long-lasting battery experience in typical applications.

Common uses include UPS backups, emergency lighting and power, security systems, medical equipment, power tools, and other devices that rely on trusted battery backup. Whether you need a dependable replacement battery for everyday use or an emergency reserve, this 12 Volt 40 Ah SLA battery is designed to meet those demands.

Need help before purchasing? Customer service is available at 1 or by email to answer questions. Buy your BS Battery B12-40 replacement battery with confidence today—secure a long-lasting battery at a competitive price and benefit from fast shipping and a minimum 1 year warranty.

Click to purchase and get a high-performance battery replacement that ensures reliable, long-lasting battery power.



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