FYI: battery charger tests with V vs. t and I vs. t plots

This link might be interesting to some of you. On it there are tests showing the V and I plots for some 12V battery chargers from Noco, Ctek, Battery Tender, and others.

https://bobistheoilguy.com/forums/threads/battery-charger-testing-results.336207/

All the tests are on the first page (as I write this). Unfortunately the initial battery state is not the result of a known discharge, and the author doesn't seem to have burned off the surface charge before starting, so the voltage at start may not be a good SOC indication, and several different test batteries were used. I would like to have seen the integrated Ah values from the I vs. t curves, but the author didn't do that. Anyway, some data on these chargers is better than no data.

The HF 63350 "Viking" charger I have, which it says is "4A", typically only charges at 2A for a short time (minutes, not hours, on both AGM and flooded), and then drops straight down to 1A. I have only seen it hit 4A once, and that was when charging a pair of parallel truck batteries in a diesel F350. Anyway, the CTEK MUS 4.3 is on paper a charger with pretty similar characteristics, yet it starts at 4A for about 2.5 hours, and then the current it uses decays to a constant (formula like: Istart*exp(-t/T) + Ibase). This all goes to show that a comparison of chargers based just on their written specifications tells a person basically nothing about what the charger is actually going to do.

 

2021 is when the thread started, the test data was added to the front of the thread at various later dates.

But you have a valid point. There is nothing to stop a manufacturer from selling a model "X1000" for 10 years, with different electronics in it each year. So even if you have the "same model" charger as one tested in 2022, it might not actually be the same device.