Li-Ion Battery Capacity Evaluation

In the first approximation, we can present a Li-Ion battery as a jar with the following parts:

1. Consumed volume
2. Remaining volume

But why is this not true, and why can't we consume all the charge from the battery?

Custom Arduino Driver for Battery Gas Gauging Device BQ28Z610

This is a driver for Arduino that provides functions to interface with the BQ28Z610 battery gas gauge device over I2C protocol. With this driver, you can operate the BQ28Z610 device via the serial port from your computer using Arduino.

Functions were implemented based on the documentation:

• Technical Reference Manual (c) Texas Instruments, Literature Number: SLUUA65E, https://www.ti.com/lit/ug/sluua65e/sluua65e.pdf

Not all functions described in the Technical Reference Manual were implemented, but most of them.

The driver also includes some additional service functions for more usability.

Texas Instruments Battery Gas Gauging Device BQ28Z610 JBL XTREME 2 Data Flash Content

This dump of Data Flash was made for the device after few years of active usage.

What Does the Texas Instruments BQ28Z610 Device Function "12.2.19 AltManufacturerAccess() 0x0028 Lifetime Data Reset" Do?

It only writes the following Data Flash values:

0x4280: (I2) [Lifetimes / Voltage / Cell 1 Max Voltage] = 0
0x4282: (I2) [Lifetimes / Voltage / Cell 2 Max Voltage] = 0
0x4284: (I2) [Lifetimes / Current / Max Charge Current] = 0
0x4286: (I2) [Lifetimes / Current / Max Discharge Current] = 0
0x4288: (I1) [Lifetimes / Temperature / Max Temp Cell] = -128
0x4289: (I1) [Lifetimes / Temperature / Min Temp Cell] = 127

Gas Gauging Device BQ28Z610 Learning Cycle: Practical Guide

There are standard instructions on the internet about how to perform a learning cycle, but in this article, I will explain how to practically perform a learning cycle in a real case for the used Device and why it may fail.

The data I have collected during this journey is attached via the link at the end of the article.

Disclaimer: The author of this article has no affiliation with Texas Instruments. This article is written for the purpose of personal and independent research by the author. It may contain mistakes and subjective judgments made by the author. The author disclaims any responsibility for the consequences of using the information provided in the article. The materials of the article are distributed as-is. Each person who uses the materials in practice assumes full responsibility for the consequences thereof.

Let's take the used Gas Gauging Device BQ28Z610 and connect some new batteries to it.

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BQ28Z610 Stop Battery Charging at a Specific Percentage

 

In this article I'll show you how to configure Texas Instruments Gas Gauging Device BQ28Z610 to stop charging at 60% SOC and resume at 55%.

This feature can be useful when your device is mostly connected to the power supply, causing the batteries to remain almost always fully charged, which negatively affects their lifespan. To extend the life of the batteries, it is much better to maintain a constant charge level at around 60%. You might have seen similar recommendations on your laptops.

Texas Instruments BQ28Z610 GaugingStatus()[REST] is not set

If you read the GaugingStatus()[REST] flag via the I2C protocol from the BQ28Z610 device and it never becomes high, then just check again which bit you read, because the documentation from TI has many typos, and this is one of them.

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