I used coconutBattery version 3.7 for this guide. I will update this guide if the UI changes in the future.
To get a copy of coconutBattery, head on over to the site I have included below.
Hit that download button. It should be downloading into wherever you set your downloads to download to.
Double click on the coconutBattery application.
Your Mac's info...
Your Battery info...
And lastly, your charger's info.
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