diff --git a/hosts/framenix/default.nix b/hosts/framenix/default.nix
index de8c815..feb58c5 100644
--- a/hosts/framenix/default.nix
+++ b/hosts/framenix/default.nix
@@ -35,6 +35,18 @@ in
     "amdgpu.abmlevel=1" # adaptive backlight management
   ];
 
+  # at boot by default, limit charging capacity to protect battery.
+  # Hopefully there's gonna be a standard interface to control this from the desktop at some point.
+  systemd.services.battery-charge-limit = {
+    wantedBy = [ "basic.target" ];
+    serviceConfig = {
+      Type = "oneshot";
+      ExecStart = "${lib.getExe pkgs.framework-tool} --driver portio --charge-limit 85";
+      RemainAfterExit = true;
+    };
+  };
+
+
   boot.loader = {
     systemd-boot.enable = true;
     efi.canTouchEfiVariables = true;