Dual-Lite ML21CH High Performance 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
6 Volts | 20 Ah
Terminal Type
Nut & Bolt
Replacement Dual-Lite ML21CH Battery — Compatible with Dual-Lite ML21CH
Restore dependable emergency lighting with this precision-fit replacement battery for the Dual-Lite ML21CH. Offering factory-fresh reliability and full compatibility, this battery combines AGM technology with maintenance-free, spill-proof construction to provide consistent power when safety matters most. Whether you're an electrician, building manager, or homeowner, the Dual-Lite ML21CH replacement battery delivers the trusted performance you expect from a high-performance battery solution.
Key Specifications
- Compatible Model: Dual-Lite ML21CH
- Chemistry: Absorbent Glass Mat (AGM) Technology
- Design: Maintenance-Free
- Construction: Spill Proof
- Certifications: U.L. Recognized and CE Certified
- Condition: Brand New, Factory Fresh
- Warranty: 1 Year Warranty
- Voltage: 6 Volts
- Capacity: 20 Ah
- Terminal Type: Nut & Bolt
- Brand: SigmasTek
Benefits
Built for durability and dependable service, this replacement battery provides long-lived energy storage and reliable startup under load. AGM technology delivers robust performance with lower self-discharge, strong charge acceptance, and resistance to vibration—qualities that support a long-lasting battery life in demanding environments. The maintenance-free, spill-proof design reduces upkeep and simplifies installation, making it ideal for both new equipment and replacements.
The Dual-Lite ML21CH replacement battery is especially suited to emergency lighting and emergency power applications, ensuring illumination and safety systems remain functional during outages. Other common uses include security alarms, fire alarms, medical equipment, consumer electronics, and home & garden devices. Additionally, this battery performs well in UPS systems, emergency power backups, and for tools that accept sealed lead-acid batteries. Certified by U.L. and CE and backed by a one-year warranty, it meets safety and quality expectations for professional installations.
Secure connection is simple with nut & bolt terminals, providing a reliable mechanical and electrical attachment for field service or OEM replacement. If you need assistance verifying fit or installation steps, our customer service team is ready to help by phone or email.
Ready to order your replacement Dual-Lite ML21CH battery? Purchase now to get a long-lasting, high-performance battery shipped quickly — most in-stock orders ship within 24 hours. Ensure your emergency lighting remains reliable by buying today.
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