I had a previous post on the modern day batteries. These do NOT suffer from the memory effect which was present with the old batteries. You can charge the present day lithium-ion batteries whenever you want. There’s
NO need to let it discharge 100 per cent before recharging.
Li-ion batteries work in
charge cycles. You complete one charge cycle when you’ve discharged an amount that equals 100 per cent of your battery’s capacity — but not necessarily all from one charge. You might use 75 per cent of your battery’s capacity one day, then recharge it fully overnight. If you use 25 per cent the next day, you will have discharged a total of 100 per cent, and these two days will add up to one charge cycle. Or it might take several days to complete a cycle depending on how to charge and discharge it. The batteries are designed to have a specific number of charge cycles.
I believe iPad batteries are designed to hold at least 80% of the charge after 500 cycles. Also comes with one year warranty.
Out of warranty they replace the iPad for a standard fee. Else you can replace the battery yourself, this is cheaper but it is very tricky as you can easily damage the display while trying to open it. I haven't attempted this but my teenager does this quite confidently.
