FIAMM FGC21803 High Performance Compatible Replacement Battery
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⚠️ 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 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
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
⚠️ 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 | 18 Ah
Terminal Type
Nut & Bolt
FIAMM FGC21803 Replacement Battery — Compatible with FIAMM FGC21803
Replace your FIAMM FGC21803 with a reliable, maintenance-free alternative designed for optimal performance and compatibility. This replacement battery uses Absorbent Glass Mat (AGM) technology in a sealed lead acid (SLA) construction to deliver dependable, spill-proof operation. Ideal for customers seeking a high-performance battery and a long-lasting battery replacement, the FGC21803 unit is guaranteed compatible and competitively priced.
Key Specifications
- Compatible Model: FIAMM FGC21803
- Battery Type: Sealed Lead Acid (SLA)
- Technology: Absorbent Glass Mat (AGM)
- Voltage: 12 Volts
- Capacity: 18 Ah
- Terminal Type: Nut & Bolt
- Replacement Brand: SigmasTek
- Certifications: U.L. Recognized and CE Certified
- Condition: Brand New, Factory Fresh
- Design: Maintenance-Free with Spill Proof Construction
- Warranty: 1 Year Warranty
Benefits
The FIAMM FGC21803 replacement battery provides robust, steady power with minimal maintenance. AGM technology reduces the risk of leakage and improves tolerance to vibration and shock, making this a resilient option for demanding environments. Its sealed, maintenance-free construction saves time and effort while offering safe operation in cabinets and enclosed equipment racks.
As a high-performance battery, the FGC21803 supports stable voltage output under load, which is essential for UPS systems, emergency power supplies, security and fire alarm systems, medical equipment, and a variety of portable and stationary tools. Nut & bolt terminals make connections straightforward and secure, ensuring a reliable electrical path for backup and cyclic applications. Compliance with U.L. recognition and CE certification gives added confidence in safety and manufacturing standards.
Delivered brand new and factory fresh with a 1 Year Warranty, this replacement battery is a practical option for both field replacements and planned system maintenance. If you require a long-lasting battery that matches OEM specifications and performs reliably in critical systems, this FGC21803 replacement meets those needs.
Ready to restore dependable power? Purchase the FIAMM FGC21803 replacement battery today to secure a maintenance-free, long-lasting solution for your equipment. Click to buy now and benefit from assured compatibility and reliable delivery.
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