The 1S-8S Lithium Battery Capacity Indicator is a professional-grade monitoring tool designed to give you an instant, visual representation of your battery’s health. At Electrapac, we recommend this module for anyone building custom power banks, electric vehicle (EV) battery packs, or solar storage systems where knowing the remaining charge is critical.

Product Overview

This versatile tester features a crisp Green Display that uses a "battery-frame" icon with four internal segments. It is Universal, meaning it can be configured to monitor anything from a single lithium cell (1S / 3.7V) up to a large high-voltage pack (8S / 29.6V). The module works by measuring the real-time voltage and comparing it against standard discharge curves for Li-ion batteries.

Key Features for Electrapac Customers

• Adjustable Solder Pads: Unlike single-voltage testers, this module features pads on the back labeled S1 through S8. By simply bridging the correct pad with a drop of solder, you can reconfigure the module for any pack size.

• Low Profile Design: Extremely thin and compact, making it easy to mount into the dashboard of an electric scooter or the side of a DIY battery box.

• Power Efficient: It consumes very little power. At Electrapac, we suggest wiring it through a momentary push-button so it only displays when you need to check the level, saving your battery's energy.

• Green High-Contrast Display: The vibrant green bars are easily visible in daylight, making it perfect for outdoor electric vehicle use.

Configuration & Wiring Guide

To set up your Electrapac battery tester, follow these two steps:

1. Set the Battery Series (S)

On the back of the PCB, you will see pads labeled S1, S2... S8.

• 1S (3.7V-4.2V): Solder the S1 pads together.

• 3S (11.1V-12.6V): Solder the S3 pads together.

• Important: Only solder one pair of pads corresponding to your battery's "S" count.

2. Connect to Power

1. Connect the Red (+) Terminal of the module to the Battery Positive.

2. Connect the Black (-) Terminal of the module to the Battery Negative.

Primary Applications

• Electric Vehicles: Monitoring the remaining range on e-bikes, scooters, and skateboards.

• DIY Power Banks: Adding a professional fuel gauge to your custom 18650 battery packs.

• Solar Power Storage: Keeping track of the charge level in lithium-based off-grid systems.

• RC Hobbies: A quick-check tool for Li-Po packs used in drones and RC cars.

• Field Equipment: Integrated battery monitoring for portable testing gear or medical devices.

Why Shop at Electrapac?

We ensure our Capacity Indicator Modules are calibrated for the standard 4.2V peak of Lithium-ion chemistry to ensure your "Full" reading is accurate. Visit us at for the diagnostic tools that keep your power systems transparent and reliable.