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SigmasTek  |  SKU: BW-11815

Sonnenschein S825I High Performance Replacement Battery

Sale price $20.99 USD Regular price $32.01
Shipping calculated at checkout.

➤ Meets or exceeds OEM specifications for Sonnenschein S825I compatibility

➤ Absorbent Glass Mat (AGM) technology for reliable, spill-proof performance

➤ Maintenance-free design ensures hassle-free use and long service life

➤ U.L. Recognized and CE Certified for safety and quality assurance

➤ Includes 1-year warranty and factory-fresh condition for peace of mind


📦🚀 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

6 Volts | 3 Ah

Terminal Type

F1

Sonnenschein S825I Replacement Battery — Compatible with Sonnenschein S825I

Replace your worn battery with a dependable Sonnenschein S825I replacement battery designed for emergency lighting and critical standby systems. This replacement battery delivers consistent performance, reliable recharge characteristics, and the peace of mind that comes with factory-fresh construction. Whether you need a replacement battery for emergency lighting, alarms, or medical devices, the Sonnenschein S825I (SigmasTek) offers compatibility and dependable power when it counts.

Key Specifications

  • Model Compatibility: Sonnenschein S825I
  • Replacement Brand: SigmasTek
  • Battery Type / Technology: Absorbent Glass Mat (AGM) Technology
  • Voltage: 6 Volts
  • Capacity: 3 Ah
  • Terminal Type: F1
  • Design: Maintenance-Free
  • Construction: Spill Proof
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Meets/Exceeds: OEM SLA battery specifications

Benefits

Built with AGM technology, this Sonnenschein S825I replacement battery delivers a high-performance battery solution that is maintenance-free and spill proof. The sealed design reduces the risk of leaks and corrosion, providing enhanced durability in demanding environments. As a long-lasting battery option, it resists deep discharge damage and supports repeated charge cycles for reliable standby use.

Ideal for emergency lighting systems, security and fire alarms, and medical equipment, this replacement battery supports critical applications where uninterrupted power matters. Its UL recognition and CE certification confirm compliance with key safety standards, and the brand-new, factory-fresh construction ensures you receive a product with optimal shelf life. The 1 year warranty adds an extra layer of protection and confidence in your purchase.

If you need a high-performance battery that matches Sonnenschein S825I specifications precisely, this SigmasTek replacement is engineered for compatibility and performance. Use it in UPS setups, emergency lighting arrays, alarm panels, and other systems that rely on dependable standby power.

Ready to replace your battery? Choose this Sonnenschein S825I replacement battery now for a reliable, long-lasting battery solution that keeps your critical systems up and running. Purchase today to secure dependable emergency power.


Payment & Security

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