diff --git a/apps/counter/api/serializers.py b/apps/counter/api/serializers.py
index 7cf394d..3ce2485 100644
--- a/apps/counter/api/serializers.py
+++ b/apps/counter/api/serializers.py
@@ -1,4 +1,4 @@
-from django.db.models import Q
+from django.db.models import Q, Min, Max
 from django.core.cache import cache
 from rest_framework import serializers
 from counter.models import DeviceCount, DeviceInfo
@@ -6,6 +6,22 @@ from mosquito.models import DeviceInfo as CelexDeviceInfo
 from mosquito.models import MosqPostStatistic, DevicePostStatistic
 
 
+def get_vol(device_id, cur_vol):
+    vol_min_key = '{}_vol_min'.format(device_id)
+    vol_max_key = '{}_vol_max'.format(device_id)
+    vol_min = cache.get(vol_min_key)
+    vol_max = cache.get(vol_max_key)
+    if not vol_min:
+        vol_min = DeviceCount.objects.filter(device_id=device_id).aggregate(vol_min=Min('vol'))['vol_min']
+        cache.set(vol_min_key, vol_min, 60 * 5)
+    if not vol_max:
+        vol_max = DeviceCount.objects.filter(device_id=device_id).aggregate(vol_max=Max('vol'))['vol_max']
+        cache.set(vol_max_key, vol_max, 60 * 5)
+
+    vol = 100 * (int(cur_vol) - int(vol_min)) / (int(vol_max) - int(vol_min))
+    return '{}{}'.format(round(vol, 1), '%')
+
+
 class DeviceCountSerializer(serializers.ModelSerializer):
     device_name = serializers.SerializerMethodField()
     mosq_count = serializers.SerializerMethodField()
@@ -34,16 +50,16 @@ class DeviceCountSerializer(serializers.ModelSerializer):
         return obj.csq
 
     def get_energy(self, obj):
-        return obj.vol
+        return get_vol(obj.device_id, obj.vol)
 
     def get_calc_time(self, obj):
         return obj.data_time.strftime('%Y-%m-%d %H:%M:%S')
 
     def get_device_name(self, obj):
         device_id = obj.device_id
-        cache_content = cache.get(device_id)
-        if cache_content:
-            return cache_content
+        device_name = cache.get(device_id)
+        if device_name:
+            return device_name
         qs = CelexDeviceInfo.objects.filter(device_id=device_id)
         if qs.count() > 0:
             device = qs[0]
@@ -105,7 +121,7 @@ class DeviceInfoSerializer(serializers.ModelSerializer):
 
     def get_energy(self, obj):
         if self.latest:
-            return self.latest.vol
+            return get_vol(obj.device_id, self.latest.vol)
         return 0
 
     def get_coordinate(self, obj):