Thank you for the suggestions, I contacted Deltran...
http://www.batterytender.com/Automotive/Battery-Tender-Plus-High-Efficiency.html
And they told me that their charger will work through the lighter plug only if the lighter plug is always hot, this means that you don't need the key to open the switch.
Update, I checked my car and the lighter plus is hot without the key, so I went ahead and order the battery tender and the lighter adapter, hopefully after a couple of
days will allow us to open the front hood without having to search for the elusive cable ..Ha,
Thereafter my friend will have the battery tender and keep this from happening again