手机电池内部带有ntc电阻，该电阻随电池温度变化而变化，根据ntc的这一特性，便可推算出电池温度，从而定制化手机行为。

ntc电路如下，R6106默认不贴，把电池扣上去后，形成了一个简易的分压电路，假设电池ntc电阻为R，则BAT_TEMP_ADC的电压为1.85*R/(R+47K)，BAT_TEMP_ADC的电压可以通过cpu内部的adc电路测量出来，进入反算出电阻ntc阻值R，再根据电池ntc表，推算出电池温度。

电池高温关机

http://aospxref.com/android-11.0.0_r21/xref/frameworks/base/services/core/java/com/android/server/BatteryService.java

        mShutdownBatteryTemperature = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_shutdownBatteryTemperature);

    private void shutdownIfOverTempLocked() {
        // shut down gracefully if temperature is too high (> 68.0C by default)
        // wait until the system has booted before attempting to display the
        // shutdown dialog.
        if (mHealthInfo.batteryTemperature > mShutdownBatteryTemperature) {
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    if (mActivityManagerInternal.isSystemReady()) {
                        Intent intent = new Intent(Intent.ACTION_REQUEST_SHUTDOWN);
                        intent.putExtra(Intent.EXTRA_KEY_CONFIRM, false);
                        intent.putExtra(Intent.EXTRA_REASON,
                                PowerManager.SHUTDOWN_BATTERY_THERMAL_STATE);
                        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                        mContext.startActivityAsUser(intent, UserHandle.CURRENT);
                    }
                }
            });
        }
    }

http://aospxref.com/android-11.0.0_r21/xref/frameworks/base/core/res/res/values/config.xml

<integer name="config_shutdownBatteryTemperature">680</integer>

温度过高或者过低停止充电

以展讯平台为例，高于80°c或者低于-20°c都停止充电

       cm-battery-cold = <200>;
       cm-battery-cold-in-minus;
       cm-battery-hot = <800>;
       cm-battery-temp-diff = <100>

static int cm_check_thermal_status(struct charger_manager *cm)
{
	struct charger_desc *desc = cm->desc;
	int temp, upper_limit, lower_limit;
	int ret = 0;

	ret = cm_get_battery_temperature(cm, &temp);
	if (ret) {
		/* FIXME:
		 * No information of battery temperature might
		 * occur hazadous result. We have to handle it
		 * depending on battery type.
		 */
		dev_err(cm->dev, "Failed to get battery temperature\n");
		return 0;
	}

	upper_limit = desc->temp_max;
	lower_limit = desc->temp_min;

	if (cm->emergency_stop) {
		upper_limit -= desc->temp_diff;
		lower_limit += desc->temp_diff;
	}

	if (temp > upper_limit)
		ret = CM_EVENT_BATT_OVERHEAT;
	else if (temp < lower_limit)
		ret = CM_EVENT_BATT_COLD;

	return ret;
}

static bool _cm_monitor(struct charger_manager *cm)
{
	...
	temp_alrt = cm_check_thermal_status(cm);
	if (temp_alrt) {
		cm->emergency_stop = temp_alrt;
		dev_info(cm->dev,
			"Temperature is out of range normal state, stop charging\n");
		if (!try_charger_enable(cm, false))
			uevent_notify(cm, default_event_names[temp_alrt]);
	} 
	...
}