Tell me if this is good or dangerous...

[PNjunction]

In regards to the 7ah battery, I would definitely use a small charge controller from the like of say Morningstar.

That panel seems to just meet the minimum 5% requirement, or C/20 rate: 7/20 = .350 amps. If you take it down to a 50% DOD, it might take about 2 solar days to fully recharge. I'd have to look at the solar insolation values of the Azores to be sure.

Be sure to doublecheck with your own multimeter the listed ratings - sometimes I have come across small utility panels like those that are pretty optimistic. Test for VOC and ISC.

Also, if that panel is made from crystalline chips (most likely), then you can test each module by shading them one at a time with your finger or something else, and there should be a noticeable drop in voltage. If you cover a module and you don't detect any voltage drop, then that module itself may be bad.

[inetdog]

Many small batteries have a nut and bolt. You could take any small polarized connector/plug from an electronics parts shop or possibly auto parts store (rated for 1/2 amp or more) and hardwire that to the battery and solar panel. That will reduce the chance of miss-connection.

-Bill

Other really small batteries such as alarm and emergency lighting have a tab which goes into a crimp-on female connector on the wiring harness. The better ones have different sized tabs on + and - so that you cannot hook it up wrong. But as BB said, make sure that any point at which you will routinely disconnect the system uses a polarized connector. Get the others wired up properly the first time and then never disconnect them.

[PNjunction]

Speaking of polarized connectors, be sure to doublecheck the polarity with a multimeter. An example is Harbor Freight panels quick disconnects are not the same polarity as Battery Tender charger jumpers that use the same style of quick disconnect. I found this out the hard way and was scratching my head for awhile. So when mixing and matching different vendors connectors, doublecheck them with a meter even if they seem to physically connect up just fine.