Best Power LI 750 (Fortress) UPS High Performance Replacement Battery Set
Couldn't load pickup availability
⚠️ 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.
📸 Send Your Battery Photo / Unsure? Expert Help
Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
POST YOUR IMAGE
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 | 9 AH
Terminal Type
F2
Replacement Battery Set for Best Power LI 750 (Fortress) - SigmasTek SP12-9HR (12V 9AH)
Maintain reliable backup power for your Best Power LI 750 (Fortress) UPS with this replacement UPS battery set. The pack contains two SigmasTek SP12-9HR batteries, manufactured to deliver consistent, high-rate discharge performance and dependable long-term service. If you need a proven replacement UPS battery that balances endurance and output, this high-performance UPS battery kit is an excellent fit for your Fortress unit.
Key Specifications
- Model: SigmasTek SP12-9HR
- Voltage: 12 Volts
- Capacity: 9 AH (amp-hours)
- Quantity: 2 batteries per set
- Design: High Rate Discharge Design
- Construction: Valve Regulated Spill Proof Construction
- Self-Discharge: Low Self-discharge
- Durability: High Vibration Resistance
- Certifications: U.L. Recognized and CE Certified
- Condition: Brand New, Factory Fresh
- Warranty: 1 Year Warranty
- Compatibility Note: Requires use of all existing cables and hardware from original configuration
- Labeling: SigmasTek12 Volts9 AHF2SLA Batteries (as supplied)
Benefits
- Rugged & Reliable: The valve regulated, spill-proof construction and high vibration resistance ensure these batteries tolerate real-world conditions and frequent cycling without compromise.
- Extended Service Life: Low self-discharge preserves stored energy, making this a dependable, long-lasting battery option that reduces the frequency of replacements.
- High Output Capability: With a high rate discharge design, this set functions as a high-performance UPS battery capable of supplying necessary surge power during brief outages.
- Safe & Certified: U.L. recognition and CE certification confirm manufacturing standards and safety compliance for use in regulated environments.
- Multiple Uses: While primarily a replacement UPS battery for Best Power LI 750 (Fortress) units, these batteries are also suitable for emergency power supply systems and battery-powered tools.
- Quality Tested: Technical staff reviews and tests every battery to ensure it meets or exceeds OEM specifications for reliable performance.
- Installation Reminder: Use the existing cables and hardware from your Best Power LI 750 (Fortress) when installing these replacement batteries to ensure correct and safe connection.
Order your replacement UPS battery set for the Best Power LI 750 (Fortress) today to restore dependable backup and protect critical equipment. With a one-year warranty and typical same-day shipping for in-stock items, this long-lasting battery solution offers both performance and peace of mind—purchase now to secure uninterrupted power.
-
Voltage
-
Amp Hours
-
Terminal Type
-
Length (in.)
-
Width (in.)
-
Height (in.)
-
Weight (lb.)
-
Warranty
-
Type
-
Manufacturer
-
Brand Replacement
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.



