I would suggest renting one or purchase on “A Satisfaction Guaranteed Plan”. The Cordless Tool Technology Is Very Impressive! Technology Can Be Expensive If The Tools Are Not Making More Money Versus An Occasional Use.

I Know The Challenge with a Closet full of Basic 1970 Electric Hand Tools (Serviced and Working). Naturally I have a few 1st and 2nd Generations of 2-3 Cordless Tools. Sideline Work away from Home Dictated Some Changes…

Good Luck On Your Choices!!!

" Assuming this time I can not fix it, will a battery string trimmer take a brush blade so that I can cut large weeds, tree sprouts, Virginia creeper, poison ivy, and such? "

You would need to shop for specific electric trimmers to determine that. As a preliminary guide, look at electric trimmers that have a similar horsepower to your 4-cycle Cub Cadet string trimmer. Higher-powered electric trimmers tend to run on higher voltage batteries. Some of them may have available brush blades.

I notice you mentioned tree sprouts. When I lived in Maine, tree sprouts were an ongoing problem, so I purchased the Extractigator tool for pulling tree sprouts up by the roots. I assumed when we moved to Kansas that pulling tree sprouts would no longer be a problem. I couldn't have been more wrong about that. Here we have more than one tree that propagates from wind-blown seed (Elms are the worst offender). We have weed trees everywhere, including in my garden.

If you cut a weed tree off with a trimmer, it just comes back up from the root. Actually, that applies to a lot of pest weeds. I think you will find that both Virginia Creeper and Poison Ivy will come back from the root.. So, to truly control those weeds you need to pull them out by the root. And a tool like the Extractigator is what you need. (I will take a pass on the Poison Ivy--there are chemicals that can by applied without getting too close.)

I had purchased the basic Extractigator model in Maine, and it did the trick for me, but here in Kansas with weed trees and other come-back-from-the-root weeds in great abundance, I have purchased the entire Extractigator product line, from the Baby Gator (handy for pulling "regular" weeds) to the Junior to the Big Daddy. And I am using them all. Some weeds seem to enjoy having their tops trimmed off, and you need to pull them out by the roots.

ZM (not associated with any product or vendor mentioned or linked)