diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileFetcher.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileFetcher.java
index ee9e27457..70256e07d 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileFetcher.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileFetcher.java
@@ -25,17 +25,12 @@ import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.OutputStream;
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
-import java.util.GregorianCalendar;
-import java.util.HashSet;
 import java.util.LinkedList;
-import java.util.List;
 import java.util.Locale;
 import java.util.Queue;
-import java.util.Set;
+import java.util.TimeZone;
 
 import nodomain.freeyourgadget.gadgetbridge.BuildConfig;
 import nodomain.freeyourgadget.gadgetbridge.R;
@@ -137,7 +132,7 @@ public class XiaomiActivityFileFetcher {
             isFetching = true;
             final XiaomiSupport support = mHealthService.getSupport();
             final Context context = support.getContext();
-            GB.updateTransferNotification(context.getString(R.string.busy_task_fetch_activity_data),"", true, 0, context);
+            GB.updateTransferNotification(context.getString(R.string.busy_task_fetch_activity_data), "", true, 0, context);
             support.getDevice().setBusyTask(context.getString(R.string.busy_task_fetch_activity_data));
             support.getDevice().sendDeviceUpdateIntent(support.getContext());
             triggerNextFetch();
@@ -162,12 +157,21 @@ public class XiaomiActivityFileFetcher {
     }
 
     protected void dumpBytesToExternalStorage(final XiaomiActivityFileId fileId, final byte[] bytes) {
+        final SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd'T'HHmmss", Locale.US);
+
         try {
             final File externalFilesDir = FileUtils.getExternalFilesDir();
             final File targetDir = new File(externalFilesDir, "rawFetchOperations");
             targetDir.mkdirs();
 
-            final String filename = "xiaomi_" + GB.hexdump(fileId.toBytes()) + ".bin";
+            final String filename = String.format(
+                    Locale.ROOT,  "xiaomi_%s_%02X_%02X_%02X_v%d.bin",
+                    sdf.format(fileId.getTimestamp()),
+                    fileId.getTypeCode(),
+                    fileId.getSubtypeCode(),
+                    fileId.getDetailTypeCode(),
+                    fileId.getVersion()
+            );
 
             final File outputFile = new File(targetDir, filename);
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileId.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileId.java
index 3db718cbd..dfe269783 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileId.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileId.java
@@ -58,14 +58,26 @@ public class XiaomiActivityFileId {
         return Type.fromCode(type);
     }
 
+    public int getTypeCode() {
+        return type;
+    }
+
     public Subtype getSubtype() {
         return Subtype.fromCode(getType(), subtype);
     }
 
+    public int getSubtypeCode() {
+        return subtype;
+    }
+
     public DetailType getDetailType() {
         return DetailType.fromCode(detailType);
     }
 
+    public int getDetailTypeCode() {
+        return detailType;
+    }
+
     public int getVersion() {
         return version;
     }
@@ -114,9 +126,9 @@ public class XiaomiActivityFileId {
         return getClass().getSimpleName() + "{" +
                 "timestamp=" + DateTimeUtils.formatIso8601(timestamp) +
                 ", timezone=" + timezone +
-                ", type=" + (typeName + "(" + type + ")") +
-                ", subtype=" + (subtypeName + "(" + subtype + ")") +
-                ", detailType=" + (detailTypeName + "(" + detailType + ")") +
+                ", type=" + (typeName + String.format("(0x%02X)", type)) +
+                ", subtype=" + (subtypeName + String.format("(0x%02X)", subtype)) +
+                ", detailType=" + (detailTypeName + String.format("(0x%02X)", detailType)) +
                 ", version=" + version +
                 "}";
     }
@@ -149,12 +161,12 @@ public class XiaomiActivityFileId {
 
     public enum Subtype {
         UNKNOWN(Type.UNKNOWN, -1),
-        ACTIVITY_DAILY(Type.ACTIVITY, 0),
-        ACTIVITY_SLEEP(Type.ACTIVITY,8),
-        SPORTS_OUTDOOR_RUNNING(Type.SPORTS, 1),
-        SPORTS_FREESTYLE(Type.SPORTS, 8),
-        SPORTS_ELLIPTICAL(Type.SPORTS, 11),
-        SPORTS_OUTDOOR_CYCLING(Type.SPORTS, 23),
+        ACTIVITY_DAILY(Type.ACTIVITY, 0x00),
+        ACTIVITY_SLEEP(Type.ACTIVITY, 0x08),
+        SPORTS_OUTDOOR_RUNNING(Type.SPORTS, 0x01),
+        SPORTS_FREESTYLE(Type.SPORTS, 0x08),
+        SPORTS_ELLIPTICAL(Type.SPORTS, 0x0B),
+        SPORTS_OUTDOOR_CYCLING(Type.SPORTS, 0x17),
         ;
 
         private final Type type;
@@ -182,8 +194,8 @@ public class XiaomiActivityFileId {
     public enum DetailType {
         UNKNOWN(-1),
         DETAILS(0),
-        SUMMARY(1),
-        GPS_TRACK(2),
+        SUMMARY(0x01),
+        GPS_TRACK(0x02),
         ;
 
         private final int code;