diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b142ba..78b102e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,4 +6,7 @@ project(blinky)
 
 zephyr_include_directories(inc)
 
-target_sources(app PRIVATE src/main.c)
+target_sources(app PRIVATE
+  src/main.c
+  src/battery_module.c
+)
diff --git a/boards/atguigu/mini_keyboard/mini_keyboard.dts b/boards/atguigu/mini_keyboard/mini_keyboard.dts
index e25be1b..4dd8408 100644
--- a/boards/atguigu/mini_keyboard/mini_keyboard.dts
+++ b/boards/atguigu/mini_keyboard/mini_keyboard.dts
@@ -1,6 +1,7 @@
 /dts-v1/;
 #include <nordic/nrf52840_qiaa.dtsi>
 #include "mini_keyboard-pinctrl.dtsi"
+#include <zephyr/dt-bindings/adc/adc.h>
 
 / {
 	model = "Mini keyboard";
@@ -22,6 +23,15 @@
             gpios = <&gpio1 2 GPIO_ACTIVE_LOW>;
         };
     };
+
+	vbatt: vbatt {
+		compatible = "voltage-divider";
+		io-channels = <&adc 7>;
+		output-ohms = <100000>;
+		full-ohms = <200000>;
+		power-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+		power-on-sample-delay-us = <200>;
+	};
 };
 
 &flash0 {
@@ -52,6 +62,26 @@
 	};
 };
 
+&uicr {
+	nfct-pins-as-gpios;
+};
+
+&adc {
+	status = "okay";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel@7 {
+		reg = <7>;
+		zephyr,gain = "ADC_GAIN_1_4";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 40)>;
+		zephyr,input-positive = <NRF_SAADC_AIN7>;
+		zephyr,resolution = <14>;
+		zephyr,oversampling = <4>;
+	};
+};
+
 &gpio0 {
 	status = "okay";
 };
diff --git a/prj.conf b/prj.conf
index 5f11b8f..073bab0 100644
--- a/prj.conf
+++ b/prj.conf
@@ -3,6 +3,8 @@ CONFIG_CAF_BUTTONS=y
 CONFIG_CAF_BUTTONS_DEF_PATH="buttons_def.h"
 CONFIG_GPIO=y
 CONFIG_REBOOT=y
+CONFIG_SENSOR=y
+CONFIG_ADC=y
 CONFIG_HEAP_MEM_POOL_SIZE=2048
 CONFIG_LOG=y
 CONFIG_ASSERT=y
diff --git a/src/battery_module.c b/src/battery_module.c
new file mode 100644
index 0000000..11f96ac
--- /dev/null
+++ b/src/battery_module.c
@@ -0,0 +1,181 @@
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <app_event_manager.h>
+
+#define MODULE battery_module
+#include <caf/events/module_state_event.h>
+#include <caf/events/power_event.h>
+
+#include <zephyr/device.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/sensor.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/pm/device.h>
+
+LOG_MODULE_REGISTER(MODULE, LOG_LEVEL_INF);
+
+#define VBATT_NODE DT_PATH(vbatt)
+#define BATTERY_SAMPLE_INTERVAL K_SECONDS(1)
+
+BUILD_ASSERT(DT_NODE_HAS_STATUS(VBATT_NODE, okay),
+	     "Missing /vbatt voltage-divider node in devicetree");
+
+static const struct device *const vbatt_dev = DEVICE_DT_GET(VBATT_NODE);
+static struct k_work_delayable battery_sample_work;
+static bool initialized;
+static bool running;
+
+static int sensor_value_to_mv(const struct sensor_value *value)
+{
+	return (value->val1 * 1000) + (value->val2 / 1000);
+}
+
+static int measurement_enable(bool enable)
+{
+	enum pm_device_action action = enable ? PM_DEVICE_ACTION_RESUME
+					      : PM_DEVICE_ACTION_SUSPEND;
+	int err = pm_device_action_run(vbatt_dev, action);
+
+	if (err && (err != -EALREADY) && (err != -ENOTSUP)) {
+		LOG_ERR("Cannot %s vbatt sensor (%d)", enable ? "resume" : "suspend", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static void battery_sample_fn(struct k_work *work)
+{
+	struct sensor_value voltage;
+	int err;
+
+	ARG_UNUSED(work);
+
+	if (!running) {
+		return;
+	}
+
+	err = sensor_sample_fetch(vbatt_dev);
+	if (err) {
+		LOG_WRN("Battery sample fetch failed (%d)", err);
+		goto reschedule;
+	}
+
+	err = sensor_channel_get(vbatt_dev, SENSOR_CHAN_VOLTAGE, &voltage);
+	if (err) {
+		LOG_WRN("Battery channel get failed (%d)", err);
+		goto reschedule;
+	}
+
+	LOG_INF("Battery voltage: %d mV", sensor_value_to_mv(&voltage));
+
+reschedule:
+	if (running) {
+		k_work_reschedule(&battery_sample_work, BATTERY_SAMPLE_INTERVAL);
+	}
+}
+
+static int module_init(void)
+{
+	if (!device_is_ready(vbatt_dev)) {
+		LOG_ERR("vbatt device not ready");
+		return -ENODEV;
+	}
+
+	k_work_init_delayable(&battery_sample_work, battery_sample_fn);
+
+	return 0;
+}
+
+static int module_start(void)
+{
+	int err;
+
+	if (running) {
+		return 0;
+	}
+
+	err = measurement_enable(true);
+	if (err) {
+		return err;
+	}
+
+	running = true;
+	k_work_reschedule(&battery_sample_work, K_NO_WAIT);
+
+	return 0;
+}
+
+static void module_pause(void)
+{
+	if (!running) {
+		return;
+	}
+
+	(void)k_work_cancel_delayable(&battery_sample_work);
+	(void)measurement_enable(false);
+	running = false;
+}
+
+static bool app_event_handler(const struct app_event_header *aeh)
+{
+	if (is_module_state_event(aeh)) {
+		const struct module_state_event *event = cast_module_state_event(aeh);
+
+		if (check_state(event, MODULE_ID(main), MODULE_STATE_READY)) {
+			int err;
+
+			if (!initialized) {
+				err = module_init();
+				if (err) {
+					module_set_state(MODULE_STATE_ERROR);
+					return false;
+				}
+
+				initialized = true;
+			}
+
+			err = module_start();
+			if (err) {
+				module_set_state(MODULE_STATE_ERROR);
+			} else {
+				module_set_state(MODULE_STATE_READY);
+			}
+		}
+
+		return false;
+	}
+
+	if (is_power_down_event(aeh)) {
+		if (initialized) {
+			module_pause();
+			module_set_state(MODULE_STATE_STANDBY);
+		}
+
+		return false;
+	}
+
+	if (is_wake_up_event(aeh)) {
+		if (initialized) {
+			int err = module_start();
+
+			if (err) {
+				module_set_state(MODULE_STATE_ERROR);
+			} else {
+				module_set_state(MODULE_STATE_READY);
+			}
+		}
+
+		return false;
+	}
+
+	__ASSERT_NO_MSG(false);
+	return false;
+}
+
+APP_EVENT_LISTENER(MODULE, app_event_handler);
+APP_EVENT_SUBSCRIBE(MODULE, module_state_event);
+APP_EVENT_SUBSCRIBE_EARLY(MODULE, power_down_event);
+APP_EVENT_SUBSCRIBE(MODULE, wake_up_event);