Neither "battery all" nor "battery sbs-6-000b" work

In [my stock config](https://github.com/nabijaczleweli/topfig/blob/master/.config/i3status/config) I have
```perl
order += "battery all"

battery all {
format = "%status %percentage %remaining"
low_threshold = "5"

threshold_type = "time"
}
```
which no longer works, and yields `{"name":"battery","markup":"none","full_text":"No battery"}`.

Categorically untrue – see #521.

The manual says
```
To show an aggregate of all batteries in the system, use "all" as the number. In
this case (for Linux), the /sys path must contain the "%d" sequence. Otherwise,
the number indicates the battery index as reported in /sys.
```
but I don't see such an "index" attested at all (via `grep -i index *`).

So somehow `battery all` doesn't find any batteries in my two power supplies – `CROS_USBPD_CHARGER` with type=USB and `sbs-6-000b` with type=Battery.

---

This means I need to configure this battery explicitly presumably.

```perl
order += "battery sbs-6-000b"

battery sbs-6-000b {
format = "%status %percentage %remaining"
low_threshold = "5"

threshold_type = "time"
}
```
yields `{"name":"battery","instance":"/sys/class/power_supply/BAT0/uevent","markup":"none","full_text":"No battery"}`.
(Same for `battery "sbs-6-000b" {`.)

No clue where it got "BAT0" given the explicit configuration of "sbs-6-000b", accepted with no warnings or errors.

The manual says
```
If your battery is represented in a non-standard path in /sys, be sure to
modify the +path+ property accordingly, i.e. pointing to the uevent file on
your system.
```
but the path to my battery is perfectly standard, matching the `sbs-%s` (where %s is the name (address) of the device itself) format. You could make this argument for some device-specific drivers, but this isn't one them.
Is this somehow bizarrely nomenclaturally married to some specific driver?

But indeed,
```perl
order += "battery sbs-6-000b"

battery sbs-6-000b {
path = "/sys/class/power_supply/sbs-6-000b/uevent"

format = "%status %percentage %remaining"
low_threshold = "5"

threshold_type = "time"
}
```
works, but I don't really see what the point of the argument to `battery` is, then.