8.5 portable dvd player..I sent it to my family in Cuba, but I did not have any manual... They are asking me about the battery if needs to be charged every day or probably if it is used with the cord (in the house) the battery does not need to be charged... Do you have some manual about it?

SOURCE: Mintek MDP1760 Portable DVD Player

You can download the user guide from: here

SOURCE: Need replacement battery

http://www.1800customersupport.com/products.aspx?type=pad&view=107&p=71&sc=5
that link will take you to buy a replacement for 28.00. It may seem like a lot but its worth it in the long run.

SOURCE: Insignia portable dvd NS Pdvd8 need battery

Hey redhouse2,

Because Insignia® is a brand primarily carried by Best Buy™ stores, there are two basic ways that you should be able to obtain a replacement battery: by contacting Insignia® technical support, or by ordering a replacement through Best Buy Partsearch.

You may always reach Insignia® by calling their toll-free hotline at (877)-467-4289. If you would prefer a self-service option, simply visit the www.Bestbuy.com website, and follow the link at the bottom of the page that says "Order Parts." Additionally, you may always contact a Partsearch agent by calling our toll-free hotline at 888-Best-Buy (888-237-8289), and requesting to speak with a parts specialist.

Please keep in mind that while some third-party companies may carry compatible batteries for this model, if your DVD player is still under the manufacturer's warranty (or a Best Buy Performance Service Plan) you may wish to seek the replacement part through Insignia® or Best Buy™ first to avoid any unnecessary charges.

Hope this helps you out.

Sincerely,
Aaron
Go Ahead. Use Us.

SOURCE: craig portable dvd player

You can buy a new one by clicking on the hyperlink:
buy replacement ac adapter power charger cord for Criag portable dvd player

SOURCE: need help charging my mintek dvd player battery

The way the battery is usually charged is by plugging it into the player and plugging the player into the a/c outlet. Do not use the player, Just allow the player to charge the battery. The way you tell if the charging is working is the light on the front will usually be a red color and it will be steady color or blinking while charging. When the battery is fully charged, the light will turn green or turn off . This lets you know that the battery has fully charged.To test this try using the dvd player on the battery only. Play a dvd or cd and see if the battery is working properly. I hope this information helps you with your problem.