Yes, you did. "Des livres" is "books", but as in "some/a few books or more than one book".
"I like books" has a generalization of "books": all and any of them, not only some of them.
The article for generalizations is definite in French: J'aime les livres.
By nature, all verbs of appreciation (aimer, aimer bien, adorer, préférer, apprécier, détester, haïr, respecter, admirer) have this ability to introduce a general object, be it countable or not, singular or plural, material or not.
J'aime/Je déteste la musique, le chocolat, les histoires d'amour".
It is not absolutely impossible, but certainly not the first meaning of this sentence:
- "J'aime les livres" primarily means "I like books" - as a category of things, books in general, all books.
The reason is that the direct object of an appreciation verb (aimer, aimer bien, adorer, apprécier, préférer, détester, haïr, respecter, admirer) is understood as a generality, be it a category, a concept or "things in general", which need a definite article (le, la, l', les).
You can understand the first part as "I like the (specific) books", but I think that the French sentence would have something else to reinforce the specificity of the books, like "J'aime les livres, donc je les lis" = I like the books, so I read them or "J'aime ces livres, donc je lis" = I like these/those books, so I read.