[Cobra20646]

It's been my belief, that solder connectors do not have a "split" along the portion that accepts the wire, and not 'hollow' as to allow the wire to pass through the "crimp" area.
The one in the photo above is a solder type. As you can see, the "cup" portion of the connector can be partially filled with molton solder, and while heating the connector, a pre-tined wire can be inserted and then allowed to cool. Great mechanical and electrical properties.

I have also used crimp connectors, and after crimping, have went the additional step of soldering the connection. I've seen too many crimp connectors fail after a period of time, either by poor crimping (wimpy-crimp), corrosion, or vibration.

As mentioned above by Mike, the use of heat shrink insulation will provide moisture protection after the connection is done.

These connections may take longer than simply stripping off the insulation and crimping on a lug, but in the long run you'll appreciate a trouble free soldered connection.

- Jim -