diff --git a/simple/widgets/system_resources.lua b/simple/widgets/system_resources.lua
index f338bcc..03c2eeb 100644
--- a/simple/widgets/system_resources.lua
+++ b/simple/widgets/system_resources.lua
@@ -34,6 +34,15 @@ local bars = wibox.widget {
     layout = wibox.layout.flex.horizontal
 }
 
+function fileExists(name)
+    local f = io.open(name, "r")
+    if f ~= nil then
+        io.close(f)
+        return true
+    end
+    return false
+end
+
 function readCommand(command)
     local handle = io.popen(command, "r")
     local r = handle:read("*a")
@@ -151,12 +160,12 @@ function getBatteryCapacity()
     local capacity = 0
     for b in getBatteries() do
         if b:sub(1,3) ~= 'hid' and readCommand("cat /sys/class/power_supply/" .. b .. "/type"):match("Battery") then
-            if type(readCommand("cat /sys/class/power_supply/" .. b .. "/energy_now")) == "string" then
-                charge = charge + readCommand("cat /sys/class/power_supply/" .. b .. "/charge_now")
-                capacity = capacity + readCommand("cat /sys/class/power_supply/" .. b .. "/charge_full")
-            else
+            if fileExists("/sys/class/power_supply/" .. b .. "/energy_now") then
                 charge = charge + readCommand("cat /sys/class/power_supply/" .. b .. "/energy_now")
                 capacity = capacity + readCommand("cat /sys/class/power_supply/" .. b .. "/energy_full")
+            else
+                charge = charge + readCommand("cat /sys/class/power_supply/" .. b .. "/charge_now")
+                capacity = capacity + readCommand("cat /sys/class/power_supply/" .. b .. "/charge_full")
             end
         end
     end