From 9016c5d51d419db638abfa53d2dd004608da0b45 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20BOU=C3=89?= <lboue@users.noreply.github.com>
Date: Sat, 17 Jan 2026 11:55:44 +0100
Subject: [PATCH] Adjust battery voltage sensor display precision for Matter
 devices (#161088)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 homeassistant/components/matter/sensor.py     |  3 ++
 .../matter/snapshots/test_sensor.ambr         | 28 +++++++++----------
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/homeassistant/components/matter/sensor.py b/homeassistant/components/matter/sensor.py
index 0832675744ee..3077ff10cc64 100644
--- a/homeassistant/components/matter/sensor.py
+++ b/homeassistant/components/matter/sensor.py
@@ -442,6 +442,9 @@ DISCOVERY_SCHEMAS = [
             key="PowerSourceBatVoltage",
             translation_key="battery_voltage",
             native_unit_of_measurement=UnitOfElectricPotential.MILLIVOLT,
+            # Battery voltages are low-voltage diagnostics; use 2 decimals in volts
+            # to provide finer granularity than mains-level voltage sensors.
+            suggested_display_precision=2,
             suggested_unit_of_measurement=UnitOfElectricPotential.VOLT,
             device_class=SensorDeviceClass.VOLTAGE,
             entity_category=EntityCategory.DIAGNOSTIC,
diff --git a/tests/components/matter/snapshots/test_sensor.ambr b/tests/components/matter/snapshots/test_sensor.ambr
index f9a2a1fdf080..da5ecae23266 100644
--- a/tests/components/matter/snapshots/test_sensor.ambr
+++ b/tests/components/matter/snapshots/test_sensor.ambr
@@ -1375,7 +1375,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -1535,7 +1535,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -1748,7 +1748,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -2070,7 +2070,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -2612,7 +2612,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -2847,7 +2847,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -4137,7 +4137,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -4982,7 +4982,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -5199,7 +5199,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -5847,7 +5847,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -6313,7 +6313,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -6919,7 +6919,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -11404,7 +11404,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,
@@ -12661,7 +12661,7 @@
     'name': None,
     'options': dict({
       'sensor': dict({
-        'suggested_display_precision': 0,
+        'suggested_display_precision': 2,
       }),
       'sensor.private': dict({
         'suggested_unit_of_measurement': <UnitOfElectricPotential.VOLT: 'V'>,