Battery Monitor with TI BQ2018


I have project which among others involves a battery monitor for my lead acid batteries in my boat. I've searched for a solution with wide dynamic range for measuring current (mA to 100 A) and I found this nice piece TI BQ2018 ( that would be perfect for my needs.

However, it uses a less used proprietary communicating protocol (HDQ - and I can't find an existing Library for it. I'm an Arduino newbie and my programming skills haven't been used since the 80s, so I see this as a big challenge.

Anyone out there that has code for this? If not, I'm happy to get some guidance how to do it. Could I instead of starting from scratch change an existing Library (I2C, 1-wire etc)? Which one?

The BQ2018 seems to be a very good sensor for battery monitoring, maybe there are someone else that are interested in a wide dynamic range current sensor and get it to work with Arduino?


I am sorry that I can not directly point You to a library for it but maybe You can get some help from this article by a good friend of mine :

The article is in Swedish but there is an English summary at the end, and the whole project was presented (in English:-) in Elektor July-August 2010

Hi Crocco,

I'm trying to do exactly the same, for exactly the same application! Have so far made breakout boards and acquired components (incl the version). Progress is halted because the batteries are in the boat (it's summer here in NZ!). I'm keen to collaborate if our timelines and skills match! Kind regards K

Hi Klaus,

My boat is on land due to the winter in Sweden :(

My project involves also an RPM meter for my Yanmar engine (based on a Hall effect sensor on the flying wheel), an IR Temperature sensor for the engine to get early warning if cooling fails. This is why I started off by buying the ACS756KCA-50B current sensor to start with, combining it with a Voltage divider to measure the Voltage. When I get this working I will lay my hands on the TI BQ2018.

I'm keen on hearing how it develops for you!