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SigmasTek  |  SKU: BW-2031

APC SMART-UPS SU400 UPS High Performance Replacement Battery Set

Sale price $28.99 USD Regular price $41.08
Shipping calculated at checkout.

➤ Set of 4 high rate discharge batteries for reliable UPS backup power

➤ Valve regulated spill proof construction for safe, maintenance-free operation

➤ Low self-discharge rate keeps batteries ready for use longer

➤ High vibration resistance for enhanced durability

➤ Brand new with U.L. recognition and 1-year warranty


📦🚀 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

Replacement Battery Set for APC SMART-UPS SU400 — SigmasTek SP6-4.5 (Compatible with SU400)

Get reliable power when it matters most with this replacement UPS battery set designed for the APC SMART-UPS SU400. This kit includes four brand new SigmasTek SP6-4.5 sealed lead-acid cells (6 Volts, 4.5 AH) engineered for high rate discharge applications, delivering the performance and dependability your UPS needs. Whether you’re restoring runtime for a server closet or maintaining emergency power at a remote workstation, this high-performance UPS battery set is a cost-effective way to renew your APC SMART-UPS SU400 and help ensure uninterrupted operation.

Key Specifications

  • Compatible UPS Model: APC SMART-UPS SU400
  • Battery Model: SigmasTek SP6-4.5
  • Voltage: 6 Volts
  • Capacity: 4.5 AH
  • Quantity: 4 batteries per set
  • Terminal: F1
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Feature: Low Self-discharge
  • Feature: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Installation Note: Must reuse all existing cables and hardware from original configuration to connect the new UPS batteries

Benefits

  • Durability: Constructed with valve regulated, spill proof casing and high vibration resistance, these cells are built to withstand the stresses of daily UPS use and transportation.
  • Long Life: Low self-discharge chemistry helps these batteries hold charge during storage and extend useful service life, making this a long-lasting battery solution for your APC SMART-UPS SU400.
  • High Performance: The high rate discharge design provides strong, short-duration power output when your UPS needs rapid delivery of energy — ideal for supporting load surges and maintaining sensitive electronics.
  • Safety & Compliance: U.L. recognition and CE certification provide confidence in quality and regulatory compliance for commercial and residential installations.
  • Applications: Perfect as a replacement UPS battery for APC SMART-UPS SU400 units, and also suitable for emergency power systems and battery-powered tools that accept these cells.
  • Tested Quality: Each set is factory fresh and quality-tested to meet or exceed OEM specifications, ensuring dependable operation in critical power scenarios.

If you’re ready to restore runtime and reliability to your APC SMART-UPS SU400, order this high-performance UPS battery set today. Replace your aging cells with this dependable, long-lasting battery solution and enjoy fast shipping on in-stock orders. Buy now to keep your systems protected and powered when it counts.


Payment & Security

Payment methods

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