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SigmasTek  |  SKU: BW-11661

JohnLite 8921NS Reliable Replacement Battery

Sale price $9.44 USD Regular price $10.97
Shipping calculated at checkout.

➤ Meets or exceeds OEM SLA battery specifications for JohnLite 8921NS

➤ Uses advanced Absorbent Glass Mat (AGM) technology for reliable performance

➤ Maintenance-free and spill-proof design ensures safe, hassle-free use

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

➤ Includes a 1-year warranty and guaranteed 100% compatibility with your model


📦🚀 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 | 4.5 AH

Terminal Type

F1

JohnLite 8921NS Battery (Replacement) - Compatible with JohnLite 8921NS

Ensure your emergency lighting systems stay operational with the JohnLite 8921NS replacement battery, engineered for compatibility, reliability, and steady performance. This rechargeable Sealed-Lead-Acid (SLA) emergency lighting battery meets or exceeds the OEM specifications for the JohnLite 8921NS model, offering a maintenance-free solution that keeps exit signs and emergency fixtures ready when needed. A dependable replacement battery option for facilities that demand consistent standby power.

Key Specifications

  • Model Compatibility: JohnLite 8921NS
  • Battery Type: Rechargeable Sealed-Lead-Acid (SLA) Emergency Lighting Battery
  • Technology: Absorbent Glass Mat (AGM)
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Brand: SigmasTek
  • Voltage: 6 Volts
  • Capacity: 4.5 AH
  • Terminal Type: F1
  • Warranty: 1 Year

Benefits

Built with AGM technology, this JohnLite 8921NS replacement battery is a high-performance battery choice for emergency lighting systems. AGM cells improve charge acceptance and reduce internal resistance, helping the battery maintain reliable output during critical moments. The sealed, maintenance-free design eliminates the need for routine servicing and prevents electrolyte spills, making installation and long-term ownership simpler and safer.

Designed for durability, the battery withstands frequent charge/discharge cycles common in standby applications, delivering a long-lasting battery life that reduces replacement frequency and lifecycle costs. It is ideal for emergency lighting, exit signs, security systems, UPS backups, and portable maintenance tools that may require dependable standby power.

Certified by U.L. and CE and backed by a one-year warranty, this model provides reassurance that you’re selecting a compliant, factory-fresh replacement battery. The compact form factor and F1 terminal configuration allow fast, straightforward installation in compatible fixtures and housings.

Don’t risk an inoperative emergency lighting system—purchase this JohnLite 8921NS replacement battery today and restore reliable, long-lasting performance to your safety-critical equipment.


Payment & Security

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