diff --git a/variants/lilygo_tdeck_max/TDeckProMaxBoard.h b/variants/lilygo_tdeck_max/TDeckProMaxBoard.h
index 85b64095..9660aac7 100644
--- a/variants/lilygo_tdeck_max/TDeckProMaxBoard.h
+++ b/variants/lilygo_tdeck_max/TDeckProMaxBoard.h
@@ -39,7 +39,7 @@
 #define BQ27220_I2C_ADDR 0x55
 
 #ifndef BQ27220_DESIGN_CAPACITY_MAH
-#define BQ27220_DESIGN_CAPACITY_MAH  1500
+#define BQ27220_DESIGN_CAPACITY_MAH  1400
 #endif
 
 class TDeckProMaxBoard : public ESP32Board {