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Fortress Heat Mat Kit – Add-On Mat | Cold-Climate Heating for Lithium Batteries | Expandable to 980W
Stay Warm. Stay Powered.
The Fortress Heat Mat Kit – Add-On Mat is a peel-and-stick electric heating element designed to extend thermal protection across multiple lithium battery modules. When paired with the main Fortress Heat Mat Kit thermostat controller, this add-on mat helps ensure safe, reliable battery operation in cold environments—especially during freezing temperatures.
Whether you're building a backup system in a northern climate or expanding an indoor storage cabinet, the Heat Mat Add-On is a fast, flexible, and effective solution for keeping your batteries in their optimal operating range.
Key Features:
Cold-Weather Battery Heating: Maintains battery temperatures within the recommended range for charging and discharging, ensuring safe performance in freezing conditions.
Modular, Expandable Design: Connect up to 14 add-on mats in parallel (maximum 980W combined) to one main thermostat controller, expanding heating coverage as your battery bank grows.
Tool-Free Installation: Each mat features a peel-and-stick silicone adhesive backing—just apply directly to the battery surface for fast, secure attachment.
Optimized for eFlex Max & FlexTower Systems:Designed for indoor use with Fortress Power battery models that require additional heating in colder climates.
Applications:
Expanding Heating Coverage in Fortress Heat Mat Systems
Battery Banks in Cold Climates
Enclosed Indoor Battery Storage (e.g., Utility Closets or Cabinets)
eFlex Max & FlexTower Battery Heating Support
What’s Included:
1 × Fortress Heat Mat Add-On Heating Pad
Pre-installed Adhesive Backing
Connection Cable for Linking to Main Thermostat Controller
Installation Instructions
Specifications
Specification
Data
Power Consumption
70 W
Input Voltage
120 V
Dimensions (L × W × H)
11.4 × 15.6 × 0.1 in
Material
Silicone with 3M adhesive
Parallel Capacity
Up to 14 mats (max 980 W total)
Application
Indoor
Installation
Peel and stick, series-wired
Warranty
2 years
Shopping Guide
Power Storage & Inverter
Item / Appliance
Typical Power (W)
Usage Time (hrs)
Total Energy Needed (Wh)
Battery Size Needed (Ah) (12V System)
Inverter Size Needed (W)
LED Light Bulb (10W)
10W
5 hrs
50 Wh
4.2 Ah
100W
Phone Charging
5–10W
2 hrs
10–20 Wh
0.8–1.7 Ah
100W
Laptop Charging
50–100W
3 hrs
150–300 Wh
12.5–25 Ah
200W
Ceiling Fan
75W
6 hrs
450 Wh
37.5 Ah
150W
LED TV (32")
60W
4 hrs
240 Wh
20 Ah
150–200W
Refrigerator (Mini)
100W (avg)
8 hrs
800 Wh
66.6 Ah
300–500W
Water Pump (1HP)
750W
1 hr
750 Wh
62.5 Ah
1000W
Microwave Oven
1000W
0.5 hr
500 Wh
41.6 Ah
1200–1500W
Electric Kettle
1500W
0.3 hr
450 Wh
37.5 Ah
2000W
Key Formulas
Purpose
Formula
Example
Energy Consumption (Wh)
Watts × Hours
60W × 4 hrs = 240 Wh
Battery Capacity (Ah)
Watt-hours ÷ System Voltage (V)
240 Wh ÷ 12V = 20 Ah
Inverter Size (W)
Total Watts × 1.25 (for safety margin)
300W × 1.25 = 375W → Use 400W inverter
Total Load Power (W)
Sum of all appliance watts to be used at once
Light (10W) + Fan (75W) = 85W
Runtime (hrs) of Battery
(Battery Ah × Voltage) ÷ Total Load (W)
(100Ah × 12V) ÷ 240W = 5 hrs
How To Choose The Right Products
Need / Application
Recommended Battery
Inverter Size
Notes
Basic lighting + phone charging
50Ah – 100Ah (12V)
100W–200W
For small backup setups
Home office (laptop, fan, TV)
150Ah – 200Ah (12V or 24V)
500W – 1000W
For moderate usage with 4–6 hours of backup
Home backup (fridge, lights)
200Ah+ (24V or 48V recommended)
1000W – 1500W
Ideal for longer backups or heavier loads
Business / shop power backup
300Ah+ (48V system)
2000W – 3000W
Suitable for commercial setups or extended power outages
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