diff --git a/core/embed/sys/backup_ram/backup_ram.c b/core/embed/sys/backup_ram/backup_ram.c
index 525356aef9..b73b0e4ab6 100644
--- a/core/embed/sys/backup_ram/backup_ram.c
+++ b/core/embed/sys/backup_ram/backup_ram.c
@@ -186,6 +186,11 @@ backup_ram_status_t backup_ram_read_power_manager_data(
     return BACKUP_RAM_DATA_CHECK_ERROR;
   }
 
+  // If SoC is equal to 0.0f, battery critical flag must be set
+  if (pm_data->soc == 0.0f && !pm_data->bat_critical) {
+    return BACKUP_RAM_DATA_CHECK_ERROR;
+  }
+
   return BACKUP_RAM_OK;
 }
 
diff --git a/core/embed/sys/power_manager/stm32u5/power_manager.c b/core/embed/sys/power_manager/stm32u5/power_manager.c
index 5ce23889f4..659f390738 100644
--- a/core/embed/sys/power_manager/stm32u5/power_manager.c
+++ b/core/embed/sys/power_manager/stm32u5/power_manager.c
@@ -27,6 +27,9 @@
 #include "../stwlc38/stwlc38.h"
 #include "power_manager_internal.h"
 
+
+#pragma GCC optimize ("O0")
+
 // Global driver instance
 pm_driver_t g_pm = {
     .initialized = false,
@@ -55,7 +58,7 @@ pm_status_t pm_init(bool skip_bootup_sequence) {
   }
 
   // Initialize fuel gauge
-  fuel_gauge_init(&(drv->fuel_gauge), PM_FUEL_GAUGE_R, PM_FUEL_GAUGE_Q,
+  fuel_gauge_init(&drv->fuel_gauge, PM_FUEL_GAUGE_R, PM_FUEL_GAUGE_Q,
                   PM_FUEL_GAUGE_R_AGGRESSIVE, PM_FUEL_GAUGE_Q_AGGRESSIVE,
                   PM_FUEL_GAUGE_P_INIT);
 
@@ -76,8 +79,8 @@ pm_status_t pm_init(bool skip_bootup_sequence) {
     } else {
       // Backup RAM contain valid data
       drv->state = pm_recovery_data.bootloader_exit_state;
-      drv->fuel_gauge.soc = pm_recovery_data.soc;
-      drv->fuel_gauge_request_new_guess = false;
+      fuel_gauge_set_soc(&drv->fuel_gauge,pm_recovery_data.soc);
+
     }
 
     drv->fuel_gauge_initialized = true;
@@ -109,10 +112,6 @@ pm_status_t pm_init(bool skip_bootup_sequence) {
 void pm_deinit(void) {
   pm_driver_t* drv = &g_pm;
 
-  if(drv->fuel_gauge_initialized){
-    pm_store_data_to_backup_ram();
-  }
-
   if (drv->monitoring_timer) {
     systimer_delete(drv->monitoring_timer);
     drv->monitoring_timer = NULL;
@@ -123,6 +122,10 @@ void pm_deinit(void) {
     drv->shutdown_timer = NULL;
   }
 
+  if(drv->fuel_gauge_initialized){
+    pm_store_data_to_backup_ram();
+  }
+
   npm1300_deinit();
   stwlc38_deinit();
 
@@ -228,9 +231,9 @@ pm_status_t pm_turn_on(void) {
   }
 
   // Poll until at least single PMIC measurement is done
-  while(drv->pmic_last_update_ms == 0){
-  }
+  while(drv->pmic_last_update_ms == 0){};
 
+  // Check if device has enough power to startup
   if(drv->pmic_data.usb_status == 0x0 &&
      drv->pmic_data.vbat < PM_BATTERY_UNDERVOLT_RECOVERY_THR_V){
      return PM_REQUEST_REJECTED;
@@ -243,16 +246,16 @@ pm_status_t pm_turn_on(void) {
     return PM_REQUEST_REJECTED;
   }
 
-  irq_key_t irq_key = irq_lock();
-
   // Try to recover SoC from the backup RAM
   backup_ram_power_manager_data_t pm_recovery_data;
   backup_ram_status_t status =
       backup_ram_read_power_manager_data(&pm_recovery_data);
 
   if (status == BACKUP_RAM_OK && pm_recovery_data.soc != 0.0f) {
-    drv->fuel_gauge.soc = pm_recovery_data.soc;
+    fuel_gauge_set_soc(&drv->fuel_gauge, pm_recovery_data.soc);
   } else {
+    // Wait for 1s to sample battery data
+    systick_delay_ms(1000);
     pm_battery_initial_soc_guess();
   }
 
@@ -261,8 +264,6 @@ pm_status_t pm_turn_on(void) {
 
   drv->fuel_gauge_initialized = true;
 
-  irq_unlock(irq_key);
-
   return PM_OK;
 }
 
diff --git a/core/embed/sys/power_manager/stm32u5/power_manager_internal.h b/core/embed/sys/power_manager/stm32u5/power_manager_internal.h
index 6aa09eef01..e16ae54ec7 100644
--- a/core/embed/sys/power_manager/stm32u5/power_manager_internal.h
+++ b/core/embed/sys/power_manager/stm32u5/power_manager_internal.h
@@ -89,8 +89,8 @@ typedef struct {
   // Power source hardware state
   npm1300_report_t pmic_data;
   stwlc38_report_t wireless_data;
-  uint32_t pmic_last_update_ms;
-  uint32_t pmic_sampling_period_ms;
+  volatile uint32_t pmic_last_update_ms;
+  volatile uint32_t pmic_sampling_period_ms;
   bool pmic_measurement_ready;
 
   // Power source logical state
diff --git a/core/embed/sys/power_manager/stm32u5/power_monitoring.c b/core/embed/sys/power_manager/stm32u5/power_monitoring.c
index 6dea5e3b9b..d5a6b36ee3 100644
--- a/core/embed/sys/power_manager/stm32u5/power_monitoring.c
+++ b/core/embed/sys/power_manager/stm32u5/power_monitoring.c
@@ -27,6 +27,8 @@
 #include "../stwlc38/stwlc38.h"
 #include "power_manager_internal.h"
 
+#pragma GCC optimize ("O0")
+
 void pm_monitor_power_sources(void) {
   pm_driver_t* drv = &g_pm;
 
@@ -133,7 +135,7 @@ void pm_pmic_data_ready(void* context, npm1300_report_t* report) {
     drv->pmic_sampling_period_ms = PM_BATTERY_SAMPLING_PERIOD_MS;
   } else {
     // Timeout, reset the last update timestamp
-    drv->pmic_sampling_period_ms = drv->pmic_last_update_ms - systick_ms();
+    drv->pmic_sampling_period_ms = systick_ms() - drv->pmic_last_update_ms;
   }
 
   drv->pmic_last_update_ms = systick_ms();