diff --git a/src/main.c b/src/main.c
index 157c0c4..13daebf 100644
--- a/src/main.c
+++ b/src/main.c
@@ -77,6 +77,12 @@ typedef struct {
         StStr message;
 } Tel;
 
+typedef struct {
+        float wh_used;
+        float wh_total;
+        long previous_ms;
+} Bat_state;
+
 void win_init_int(StInt *st) {
         st->lwin = newwin(st->height, st->width, st->starty, st->startx);
         box(st->lwin, 0, 0);
@@ -150,15 +156,20 @@ void read_uart(Tel *t, int fd, SerialParser *uart_str) {
         }
 }
 
-void calc_data(Tel *t) {
+void calc_data(Tel *t, Bat_state *b, long now) {
         t->power.data = (int)(t->tens.data * t->amp.data);
         t->speed.data = (int)(t->rpm.data * 0.017f);
+        t->bat.data = (int)((b->wh_total - b->wh_used) * 100 / b->wh_total);
 
         if (t->speed.data > 0) {
                 t->eff.data = (float)t->power.data / (float)t->speed.data;
         } else {
                 t->eff.data = 0.0f;
         }
+
+        long dt = now - b->previous_ms;
+        b->previous_ms = now;
+        b->wh_used += (float)t->power.data * (float)dt / 3600000.0f;
 }
 
 long now_ms(void) {
@@ -407,6 +418,8 @@ int main(int argc, char **argv) {
         struct termios uart_str;
         SerialParser uart_parser = {0};
 
+        Bat_state bat_state = {0, 1000, 0};
+
         while ((option = getopt(argc, argv, "d:hfcu")) !=-1) {
                 switch (option) {
                         case 'd' :
@@ -531,6 +544,8 @@ int main(int argc, char **argv) {
 
         long t100 = 0;
         int ch = ERR;
+        long now = now_ms();
+        bat_state.previous_ms = now;
 
         while(1) {
                 ch = tolower(getch());
@@ -544,11 +559,11 @@ int main(int argc, char **argv) {
                                 } else {
                                         if (use_can) read_can(&tel, soc);
                                         if (use_uart) read_uart(&tel, uart_fd, &uart_parser);
-                                        calc_data(&tel);
+                                        calc_data(&tel, &bat_state, now);
                                 }
                                 break;
                 }
-                long now = now_ms();
+                now = now_ms();
                 if (now - t100 >= 100 * delay) {
                         win_int(&tel.speed, use_color);
                         win_int(&tel.rpm, use_color);