diff --git a/TODO b/TODO
index 8d0a4dabcf..159d540cea 100644
--- a/TODO
+++ b/TODO
@@ -19,6 +19,21 @@ Janitorial Clean-ups:
 
 Features:
 
+* beef up s2h to implement a battery watch loop: instead of entering
+  hibernation unconditionally after coming back from resume make a decision
+  based on the battery load level: if battery level is above a specific
+  threshold, go to suspend again, only hibernate if below it. This means we'd
+  stick to suspend usually, but fall back to hibernation only when battery runs
+  empty (well, subject to our sampling interval). Related to this, check if we
+  can make ACPI _BTP (i.e. /sys/class/power_supply/*/alarm) work for us too,
+  i.e. see if it can wake up machines from suspend, so that we could resume
+  automatically when the system is low on power and move automatically to
+  hibernation mode. (see
+  https://uefi.org/sites/default/files/resources/ACPI%206_2_A_Sept29.pdf
+  section 10.2.2.8 and
+  https://docs.microsoft.com/en-us/windows-hardware/design/device-experiences/modern-standby-wake-sources
+  at the end).
+
 * add an explicit "vertical" mode to format-table, so that "systemctl
   status"-like outputs (i.e. with a series of field names left and values
   right) become genuine first class citizens, and we gain automatic, sane JSON
diff --git a/man/systemd-sleep.conf.xml b/man/systemd-sleep.conf.xml
index 3311a046ca..a6949b0c3b 100644
--- a/man/systemd-sleep.conf.xml
+++ b/man/systemd-sleep.conf.xml
@@ -168,11 +168,10 @@
       <varlistentry>
         <term><varname>HibernateDelaySec=</varname></term>
 
-        <listitem><para>The amount of time in seconds
-        that will pass before the system is automatically
-        put into hibernate when using
-        <citerefentry><refentrytitle>systemd-suspend-then-hibernate.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
-        </para></listitem>
+        <listitem><para>The amount of time the system spends in suspend mode before the system is
+        automatically put into hibernate mode, when using
+        <citerefentry><refentrytitle>systemd-suspend-then-hibernate.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. Defaults
+        to 2h.</para></listitem>
       </varlistentry>
     </variablelist>
   </refsect1>
diff --git a/src/shared/sleep-config.c b/src/shared/sleep-config.c
index f3c54f5ca1..26ed4776b9 100644
--- a/src/shared/sleep-config.c
+++ b/src/shared/sleep-config.c
@@ -82,7 +82,7 @@ int parse_sleep_config(SleepConfig **ret_sleep_config) {
         if (!sc->hybrid_states)
                 sc->hybrid_states = strv_new("disk");
         if (sc->hibernate_delay_sec == 0)
-                sc->hibernate_delay_sec = 180 * USEC_PER_MINUTE;
+                sc->hibernate_delay_sec = 2 * USEC_PER_HOUR;
 
         /* ensure values set for all required fields */
         if (!sc->suspend_states || !sc->hibernate_modes