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[ROOT] ACCA: Control Charging Limits & Protect Battery Life on Android

oosteup
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Android
[ROOT] ACCA Điều Chỉnh Thông Số Sạc Pin Điện Thoại Androids

Lithium-ion and Li-Po batteries in smartphones degrade rapidly due to two primary stressors: sustained elevated temperatures and high-voltage saturation when held at 100% capacity (especially during overnight charging or intense gaming sessions while plugged in). To solve this issue at the hardware level, the open-source ACC (Advanced Charging Controller) daemon and its native graphical interface AccA provide rooted Android users with direct control over the Linux kernel power supply sysfs switches.

Quick Overview & Key Capabilities of ACC / AccA
  • Active Battery Wear Prevention: Automatically halts charging at a designated safe threshold (such as 80% or 85%) and resumes only after the battery drops to a lower limit (e.g., 70%), eliminating continuous high-voltage chemical stress at 4.35V – 4.4V.
  • Bypass Charging / Idle Mode: Routes power directly from the external wall charger to the motherboard, display, and SoC without charging or discharging the battery cells, keeping thermals cool during extended gaming.
  • Thermal Protection & Cool Down: Temporarily interrupts charging when battery temperature exceeds 40°C, preventing battery swelling and thermal runaway risks.
  • Deep Discharge Protection: Safely powers down the device at 2% – 3% to avoid dangerous cell voltage drops and sudden shutdown damage.

1. Why Smartphone Batteries Degrade & How ACC Protects Them

Smartphone Lithium-ion battery longevity is measured in charge cycles — typically lasting between 500 and 800 full cycles before maximum capacity drops below 80%. A full cycle represents charging and discharging 100% of the rated capacity.

However, chemical wear is not linear across all voltage levels:

  1. High-Voltage Chemical Stress: When charging between 80% and 100%, individual cell voltage rises sharply from 4.0V to over 4.35V. Holding this peak voltage for hours accelerates solid electrolyte interphase (SEI) degradation and increases internal cell resistance.
  2. Parasitic Loads (Gaming While Charging): Running demanding games while charging forces the power management IC to supply current to a high-power SoC while simultaneously charging the battery. Temperatures climbing past 42°C under active charging can reduce battery health drastically within months.

How ACC operates: Unlike simple play store monitor apps that merely beep when full, ACC operates with superuser root privileges. It writes directly to hardware-level kernel sysfs nodes (such as /sys/class/power_supply/battery/charging_enabled). When the target threshold is hit, ACC disables charging at the hardware PMIC controller level.

2. Charging Management Comparison on Android

The table below highlights the differences between stock manufacturer charging and granular control via ACCA:

Feature / Metric Stock Charging OEM Battery Protection ACC / AccA (Root Module)
Charge Cutoff Threshold Always charges to 100% with trickle charge. Fixed at 80% or 85% (only on select Samsung, Sony, ROG devices). Freely configurable to any exact percentage (e.g., stop at 80%, resume at 70%).
Bypass / Idle Mode Unsupported; current always flows through battery. Limited to select dedicated gaming phones in Game Space mode. Supported across most Android devices with compatible kernel power nodes.
Thermal Throttling Only slows charging rate under extreme heat (45°C+). Displays a warning notification while continuing trickle charge. Completely halts charging at customizable thresholds (e.g., 40°C) until cooled.
Deep Discharge Cutoff Shuts down at 0% (risks low-voltage lock). Shuts down at 0%. Safely initiates graceful shutdown at 2%–3% to preserve base cell voltage.
Requirements Standard on all Android devices. Dependent on brand and ROM version. Root access required (Magisk, KernelSU, or APatch).

3. Prerequisites & Download Links

To install and configure ACCA on your Android smartphone, verify the following prerequisites:

  • An Android device with an unlocked bootloader and root access via Magisk (v24.0+), KernelSU, or APatch.
  • A file manager capable of extracting ZIP archives (e.g., ZArchiver or default system file manager).

ACC Module & AccA App Package v2021.11.3

File Size: ~5.8 MB | Format: ZIP & APK | Extraction Password: osteup

Download via Google Drive Download via MediaFire
Package Contents: After extracting with password osteup, you will see two files:
  • Advanced_Charging_Controller_(ACC)-v2021.11.3.zip: The core flashable Magisk module containing daemon binaries.
  • AccA_Base.apk: The graphical user interface. Only install this APK manually if the AccA app icon does not automatically appear in your app drawer after rebooting.

4. Step-by-Step Installation & Recommended Setup

Follow these steps to flash the module and configure optimal thresholds:

Step 1: Flash the Module in Magisk / KernelSU

  1. Open the Magisk application (or KernelSU/APatch manager).
  2. Navigate to the Modules tab in the bottom right corner and tap Install from storage.
  3. Select Advanced_Charging_Controller_(ACC)-v2021.11.3.zip from your download location.
  4. Wait for the flashing process to finish until you see Done, then tap Reboot.

Step 2: Grant Superuser Privileges to AccA

Once your phone restarts, locate and open the AccA app from your home screen or app drawer. When prompted by the Superuser dialogue, tap Grant / Allow to permit kernel-level configuration writes.

Step 3: Configure Recommended Battery Protection Profiles

Navigate to Settings inside AccA and configure the following parameters for balanced daily longevity:

Setting Recommended Value Technical Function
Stop Charging At 80% or 85% Stops charging before cells enter high-voltage saturation (>4.2V), extending lifespan up to 3x.
Resume Charging At 70% or 75% Creates a 10% hysteresis buffer to avoid rapid on/off switching every time 1% drains.
Shutdown Limit 2% or 3% Proactively triggers safe shutdown before severe undervoltage locks the battery cell.
Temperature Limit 40°C Pauses charging if battery thermals rise above 40°C and resumes once cooled below 37°C.
Prioritize Idle Mode (Bypass) Enabled If hardware-compatible, powers the phone directly from AC power without cycling the battery.

Step 4: Check ACC Status via Terminal (Optional)

If you have Termux or ADB access on your computer, verify that the daemon is active with the following command:

terminalbash
su -c "acc -i"

This command outputs real-time charging status, battery temperature, cell voltage in millivolts, current draw in milliamps, and the active hardware control switch.

5. Critical Safety Precautions

Important Hardware Warnings:
  • Charging Current & Voltage Limits: Do not artificially increase the maximum current (mA) or voltage (mV) beyond factory charger and battery ratings unless you are an electrical engineer familiar with PMIC schematics. Excessive forced charging voltage can cause hardware failure.
  • Cool Down Feature: This setting briefly pauses charging for a few seconds every few minutes. If charging seems too slow during an urgent recharge, temporarily disable this mode in AccA.

6. Frequently Asked Questions (FAQ)

Does limiting charging to 80% really extend smartphone battery health?

Yes, significantly. Electrochemical studies (such as those published by Battery University) show that keeping battery capacity between 20% and 80% reduces high-voltage cathode stress. A battery capped at 80% charge can achieve 1,500 to 2,000 cycles before degrading to 80% health, compared to only 500 cycles when constantly topped up to 100%.

How do I verify if my phone supports Bypass Charging (Idle Mode)?

In the AccA application, select "Test battery idle mode". If the battery percentage stays constant while the charging icon remains connected and the phone operates normally under load, your device kernel and charging controller support true bypass charging.

What should I do if my phone experiences a bootloop after flashing?

ACC runs primarily in userspace and almost never induces bootloops. However, if any startup issue occurs, boot into custom recovery (TWRP/OrangeFox), open the built-in File Manager, delete the directory at /data/adb/modules/acc, and reboot.

Can I use AccA without rooting my Android device?

No. Controlling hardware charging circuits requires direct write access to kernel sysfs nodes located in the protected root system partition. Unrooted Play Store apps can only sound an alarm when full; they cannot cut electrical charging current.

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