And that is my point. I have an issue with that.

If the charger is measuring charge current accurately, and if somehow it magically knows how well the battery is charged in the first place, then OK, the charger's display is marginally accurate.

But if all it's doing it measuring terminal voltage, or EVEN if it is measuring terminal voltage AND charge current, then the reading is misleading. In such cases, the display is really "% of charge the battery is capable of at it's current age". My point: If the battery is in new condition, then you have 87% of rated charge. If the battery has degraded, then you have 87% of the charge is it CAPABLE of. SO it's 87% of a number less than rated capacity. And I dont give a damn what the owner's manual (written by the marketing department*) claims.

I know how batteries work and I know how so called "battery analyzers" work - and they don't display as much as they claim. Even our $600 "intelligent" chargers at work are not capable of all that great accuracy, it is the technician's job to interpret the display. No experienced tech actually takes the numbers at face value. See why my batteries (in the bike, car and truck) get replaced at 48 months?



*When I was with corporate, I was disgusted to learn that marketing took engineering's manuals and revised them before distribution to the customer.