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SigmasTek  |  SKU: BW-14038

FirstPower FP640K High Performance Replacement Battery

Sale price $7.99 USD Regular price $10.50
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced durability

➤ Maintenance-free and spill-proof design for hassle-free use

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

➤ Brand new and factory fresh to ensure optimal performance

➤ 1-year warranty for reliable 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 | 4.5 AH

Terminal Type

F1

FirstPower FP640K Replacement Battery — Compatible with FirstPower FP640K

This replacement battery is designed specifically for the FirstPower FP640K and delivers reliable, consistent power for critical applications. If you need a dependable, maintenance-free power source that meets or exceeds OEM SLA battery specifications, this FirstPower FP640K replacement battery is engineered for performance and reliability. It’s an ideal long-lasting battery option when you require a high-performance battery to restore equipment uptime quickly and economically.

Key Specifications

  • Model: FirstPower FP640K
  • Replacement for: OEM SLA battery
  • Chemistry: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand (replacement): SigmasTek
  • Voltage: 6 Volts
  • Capacity: 4.5 AH
  • Terminal Type: F1

Benefits

Choosing this replacement battery means opting for durability and dependable service life. The AGM technology provides low internal resistance and better charge acceptance, which helps the battery deliver consistent, high current when needed. As a high-performance battery, it is designed to resist vibration, offer leak-proof operation, and operate reliably across a range of temperatures—features that contribute to a long-lasting battery life in daily use.

The maintenance-free design removes the hassle of periodic water addition and minimizes downtime associated with battery upkeep. Certifications such as U.L. recognized and CE certified give added assurance for safe, approved operation in consumer and professional environments. Backed by a 1 year warranty, the FP640K replacement battery gives you confidence in both product quality and post-purchase support.

Typical applications for this replacement battery include UPS systems, emergency lighting, security systems, alarm panels, medical devices, and a variety of small backup power systems where reliable SLA performance is required. It also performs well in portable tools and equipment that call for a compact, rechargeable SLA pack.

Ready to restore power and performance? Order this FirstPower FP640K replacement battery now and get a high-performance battery solution that’s built to last. Purchase today to secure reliable backup power and fast delivery.


Payment & Security

Payment methods

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