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SigmasTek  |  SKU: BW-4921

BS Battery UPS12-3.5 High Performance Replacement Battery

Sale price $19.19 USD Regular price $27.82
Shipping calculated at checkout.

➤ Compatible replacement for BS Battery UPS12-3.5 model

➤ Brand new, factory fresh sealed lead acid battery

➤ Meets or exceeds OEM SLA battery specifications

➤ Includes minimum one year warranty and UL listing

➤ Ships within 24 hours, in stock for fast delivery


📦🚀 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 | 3.5 Ah

Terminal Type

F2

SigmasTek Replacement for BS Battery UPS12-3.5 — Compatible with BS Battery UPS12-3.5

This SigmasTek replacement UPS battery is engineered specifically for the BS Battery UPS12-3.5, delivering dependable compatibility, strong performance, and proven reliability. As a brand new, factory-fresh rechargeable sealed lead acid (SLA) unit, it meets or exceeds OEM SLA battery specifications and provides a practical, cost-effective way to restore your UPS to like-new operation. If you need a long-lasting battery that safeguards critical equipment, this replacement UPS battery is a trusted choice.

Key Specifications

  • Compatible UPS Model: BS Battery UPS12-3.5
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 3.5 Ah
  • Chemistry: Rechargeable Sealed Lead Acid (SLA)
  • Terminal Type: F2
  • Certification: UL listed
  • Condition: Brand New, Factory Fresh
  • Warranty: Minimum 1 Year Warranty
  • Meets/Exceeds: OEM SLA battery specifications
  • Shipping: In stock and typically shipped within 24 hours

Benefits

Designed for durability and consistent power delivery, this high-performance UPS battery provides the long service life and high discharge capability you expect from premium replacements. The rechargeable sealed lead acid design reduces maintenance and prevents spills, while UL listing verifies safety and manufacturing quality. Whether you are replacing an old battery in a home office UPS, supporting emergency power systems, or keeping battery-powered tools ready for use, this long-lasting battery gives you reliable runtime and peace of mind.

Users will appreciate the dependable voltage stability during critical shutdowns and the reduced self-discharge that helps preserve capacity between uses. As a true replacement UPS battery for the BS Battery UPS12-3.5, it delivers consistent, high-performance UPS support and helps extend the life of your UPS unit without sacrificing safety or reliability.

For assistance in selecting the correct BS Battery replacement SLA battery, our customer service team is available at 1 or by email. We guarantee 100% compatibility with your BS Battery UPS12-3.5 model and the best price on the market.

Ready to upgrade? Buy your BS Battery UPS12-3.5 replacement battery with confidence today — get a high-performance UPS battery and a long-lasting battery solution shipped quickly.


Payment & Security

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