Seeking Feedback on Your Interest in Roadtesting a Battery Fuel Gauge Board

i am interested, but this is completely new to me, i don't know if i'm missing something, but, is fuel gauge in this context referring to measuring the remaining capacity of a battery?(this without having looked at the datasheet or anything, just from the title and quick read of what Randall wrote) or is this something to do with fuel as in combustible fuel? this being something new to me is a big part in why i'm interested, tho i'm not sure how interested would nordic be in having a newbie roadtest this without any prior knowledge!

edit: now having read more on this board, i'm definitely interested in applying. after my bike's battery died, i've been manually characterising the individual cells in what's been a very tedious process to try to rebuild the battery itself. It would be cool to see how this board does it, even if it's for much lower capacity batteries than a bike's

i am interested, but this is completely new to me, i don't know if i'm missing something, but, is fuel gauge in this context referring to measuring the remaining capacity of a battery?(this without having looked at the datasheet or anything, just from the title and quick read of what Randall wrote) or is this something to do with fuel as in combustible fuel? this being something new to me is a big part in why i'm interested, tho i'm not sure how interested would nordic be in having a newbie roadtest this without any prior knowledge!

edit: now having read more on this board, i'm definitely interested in applying. after my bike's battery died, i've been manually characterising the individual cells in what's been a very tedious process to try to rebuild the battery itself. It would be cool to see how this board does it, even if it's for much lower capacity batteries than a bike's

Fuel gauges are the thing that give you the battery charge percentage from past and present voltage/current readings. The characterization mentioned here is only for making sure the percentages it gives back are accurate, this isn't a general purpose tool for working with batteries. It also has a capacity limit of 3000mAh.

Turns out giving an accurate percentage is really really difficult, so manufacturers don't like sharing how they did it.

There's a blog post here for a different fuel gauge chip, it contains some general info about fuel gauges, which might help understand what they are, and some example ways they can operate:

MAX17260GEVKIT# Fuel Gauge EVM - Review

That was a very good fuel gauge chip, and the approach it took, was to perform all the calculations on-chip, and doesn't require (significant) up-front configuration, apart from a few basic parameters about the battery, mostly derivable from battery datasheets.

 The Nordic chip takes a different approach from what little I've read; it doesn't perform the fuel gauge algorithm on-chip, instead, it relies on the connected microcontroller to do it, using a Nordic-supplied technique. That's no bad thing, since it means that their algorithm could be improved over time perhaps! It also requires some information up-front about the battery, and that information seems to be derived using that nPM Fuel Gauge Board. That may mean that the Nordic method is more accurate, but the Maxim algorithm has already set quite a high bar (typically, the Maxim method seems to be accurate to within a few percent), so it will be interesting to see what performance people achieve from the Nordic method. Even if the accuracy turned out to be lower, that doesn't make that feature useless. Lots of use-cases do not require extreme precision. There's a price-performance mix. And the Nordic chip does other features for a similar price to the single-purpose Maxim chip for example. 

Another point is that the Nordic chip is actually marketed as a PMIC, the fuel gauge feature is just one of the functions that it happens to support. All the PMIC features of the chip and the low-cost, are very compelling. The fuel gauge feature is (extremely welcome) icing on cake, and it will be interesting to see it in operation with different batteries, and seeing if the Nordic code can run on any microcontroller or if there is some issue (e.g. licensing).