Re: [PATCH v3 01/18] dt-bindings: power: battery: add constant-charge-current property

From: Liam Breck
Date: Tue Feb 14 2017 - 19:51:23 EST



On Tue, 14 Feb 2017 10:40:55 +0100 Quentin Schulz wrote:
> This adds the constant-charge-current property to the list of optional
> properties of the battery.
>
> The constant charge current is critical for batteries as they can't
> handle all charge currents.
>
> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
> ---
>
> added in v3
>
> Documentation/devicetree/bindings/power/supply/battery.txt | 2 ++

Is constant-charge-current dependent on the battery (e.g. capacity, nominal voltage, etc) or the
system (charger chip, input current/voltage, etc)?

It belongs in Doc.../power/supply/battery.txt if it's a characteristic of the battery.

Note, this page asserts that constant-current charging applies to NiMH batteries:
http://power-topics.blogspot.com/2016/05/constant-voltage-constant-current.html

Related properties to be added to battery.txt near-future in a patchset for the BQ24190
charger are as follows. These are not currently in enum power_supply_property, so the actual names
are still to be decided.

precharge-current-microamp:
maximum charge current during precharge phase (typically 20% of battery capacity)

termination-current-microamp (or endcharge-current):
a charge cycle terminates when the battery voltage is above recharge threshold,
and the current is below this setting (typically 10% of battery capacity)


~.~