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SigmasTek  |  SKU: BW-13681

FirstPower FP665-F2 High Performance Replacement Battery

Sale price $21.99 USD Regular price $32.15
Shipping calculated at checkout.

➤ Compatible replacement for FirstPower FP665-F2 model

➤ Uses advanced Absorbent Glass Mat (AGM) technology

➤ Maintenance-free and spill-proof design for safety

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

➤ Comes brand new with a 1-year warranty guarantee


📦🚀 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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Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
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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 | 9 AH

Terminal Type

F2

Replacement FirstPower FP665-F2 Battery — Compatible with FirstPower FP665-F2

Replace your failing battery with a compatible, high-quality replacement engineered for the FirstPower FP665-F2 model. This replacement battery is designed for dependable performance, safety, and ease of installation, delivering the reliable power you need for critical applications. For anyone seeking a high-performance battery that provides long-lasting battery life and OEM-grade compatibility, the FP665-F2 replacement is an excellent choice.

Key Specifications

  • Compatible Model: FirstPower FP665-F2
  • Replacement Brand: SigmasTek
  • Battery Type: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Voltage: 6 Volts
  • Capacity: 9 AH (Ampere-hours)
  • Terminal Type: F2
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

The FP665-F2 replacement battery offers robust durability and consistent output, suited for both standby and cyclic applications. AGM construction provides superior charge acceptance, reduced maintenance, and resistance to vibration and shock — all important for equipment that sees regular use or must remain operational during power events. The maintenance-free, spill proof design eliminates the need for routine electrolyte checks and reduces installation risks.

Safety certifications, including U.L. recognition and CE marking, confirm the battery meets international standards for quality and safety. The 6 Volt, 9 AH capacity is ideal for small UPS systems, emergency lighting, alarm and security panels, portable medical equipment, and a variety of other low-voltage devices that demand reliable stored energy. The F2 terminal offers a secure, easy-to-connect interface for compatible devices.

Arriving brand new and factory fresh, this replacement battery includes a 1 year warranty to protect your purchase and reduce concerns about early defects. It’s a cost-effective way to extend the life of your FirstPower FP665-F2 device and avoid costly downtime.

Don’t wait until a power failure affects your system. Purchase this FirstPower FP665-F2 replacement battery today to get a reliable, high-performance battery that provides long-lasting battery life and trusted compatibility. Add it to your cart now and secure dependable backup power.


Payment & Security

Payment methods

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