Problems charging led light cube seat

[jme lynne]

If anyone can help I have a color changing led light cube seat/stool & I can't find any info or replacement parts I lost the remote & charger it has a sealed lead battery 4v 4.0ah/20hr.I tried using a couple different chargers & the 4.5v seams to work but after a couple min all the led lights come on & wont shut off even when I push on/off button if anyone can tell me why it might be doing this or any help the product does not have any markings or labels to find who makes it & I can't find anything about this exact one