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SigmasTek  |  SKU: BW-5408

OPTI-UPS ES1000 / 1000ES UPS High Performance Compatible Replacement Battery Set

Sale price $51.94 USD Regular price $75.31
Shipping calculated at checkout.

➤ High-quality 12 Volt 12 Ah battery for OPTI-UPS ES1000

➤ Supports extended UPS runtime

➤ Leak-proof and maintenance-free

➤ Compact and robust build

➤ Reliable power source for critical devices


📦🚀 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

12 Volts | 12 Ah

Terminal Type

F2

SigmasTek 12 Volts 12 Ah F2 OPTI-UPS — Compatible with ES1000

Restore reliable backup power for the ES1000 with the SigmasTek 12 Volts 12 Ah F2 OPTI-UPS replacement battery. This unit emphasizes compatibility with the ES1000 model and provides the consistent performance necessary for protecting vital electronics. Whether you manage a server closet, a small office, or critical home equipment, this replacement UPS battery is crafted to deliver stable output and trustworthy recharge behavior.

Key Specifications

  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 12 Ah
  • Terminal Type: F2
  • Compatible UPS Model: ES1000
  • Product Type: OPTI-UPS replacement

Benefits

This high-performance UPS battery is intended to offer long-term dependability and strong performance under typical UPS loads. The 12 Ah capacity is a practical balance of energy and form factor, making it suitable for extended runtime scenarios while remaining compact for easy handling and installation. As a long-lasting battery alternative for the ES1000, it supports regular cycling and standby usage with stable voltage delivery.

Durability is enhanced by the quality of the F2 terminal connections and the manufacturing standards associated with the SigmasTek product line. These features reduce connection problems and lower the risk of early failure, which is important in environments where uptime is essential. The battery’s design suits emergency power applications, from network equipment and servers to critical communications gear and lighting circuits.

Typical use cases include UPS backup for small IT racks, emergency power for telephone and network infrastructure, and auxiliary power for tools and control systems that require uninterrupted DC power. Because it is a replacement UPS battery engineered for the ES1000, users can quickly bring systems back to full protective capability without replacing the entire UPS hardware.

With an eye toward affordability and longevity, this SigmasTek battery provides a cost-effective route to restoring your ES1000’s runtime and ensuring mission-critical devices remain protected during outage events.

Ready to upgrade your ES1000 backup capacity? Add this reliable, high-performance UPS battery to your cart now and secure peace of mind.


Payment & Security

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