diff --git a/ToDo.md b/ToDo.md
index b35ef5e..8f59c7d 100644
--- a/ToDo.md
+++ b/ToDo.md
@@ -8,7 +8,8 @@
   - Tertiary display: 73x21mm (2.99") [1602 Character LCD Green](https://de.aliexpress.com/item/1843542559.html) (+ accompanying parallel to I2C Adapter)
 - [x] which uC?
      - [T-Energy ESP32-S3](https://lilygo.cc/products/t-energy-s3)
-- [ ] battery
+- [x] battery
+  - use what we already have
 - [X] loading circuit
   - Integrated with uC module
 - [X] NFC reader (ISO 14443-3A) (NXP-NTAG216) (888 Bytes needed!)