the amperage is not a linear stuff as far as Lithium batteries are involved. You have three factors :
- factor 1 : the higher the amperage, the faster the battery will charge (within factor 3 brackets)
- factor 2 : if the amperage is too low, the PlayBook battery has a system that prevents it to charge. You can get a very explicit message on the screen "insufficient current" (you are outside factor 3 bracket)
- factor 3 : a given battery has a nominal bracket of use in terms of electric values. If you are outside it, the battery may get harmed.
example of factor 3 : full iPhone fake batteries, that do not have the blocking system and that will continue swallowing high current, get hot and eventually explode
I strongly advise you to use the genuine BlackBerry PlayBook chargers models. Those models can be seen at shopblackberry.com but you can buy them anywhere for half the price.
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