diff --git a/lib/cleargrass/sensor.go b/lib/cleargrass/sensor.go
index 9235cb7..73fb778 100644
--- a/lib/cleargrass/sensor.go
+++ b/lib/cleargrass/sensor.go
@@ -88,7 +88,7 @@ func ParseCleargrassSensorData(writeAPI *influxdb2_api.WriteAPI, logger *zap.Log
 				continue
 			}
 
-			battery := int(eventData[0])
+			battery := uint8(eventData[0])
 
 			point := influxdb2.NewPointWithMeasurement("battery")
 			point.SetTime(timestamp)
@@ -108,7 +108,7 @@ func ParseCleargrassSensorData(writeAPI *influxdb2_api.WriteAPI, logger *zap.Log
 				zap.String("description", description),
 				zap.String("measurement", "battery"),
 				zap.String("measurement_unit", "%"),
-				zap.Int("value", battery))
+				zap.Uint8("value", battery))
 
 		default:
 			logger.Warn("unknown event type",