1. BlackBurreh's Avatar
    I was looking at a Powerbank that has 3A per port, 4.5A overall with two ports total. Will it cause harm to the Passport battery over time, and is it safe to use? I'm assuming that it would charge faster but with increased heat.
    06-29-16 08:08 PM
  2. kkoo's Avatar
    USB charging comes in many flavors (I have design expertise in this field). The first thing to note is that chargers for micro-USB implement one of the following (a) the USB 2.0/3.1 standard charging rates of 500mA/900mA, (b) USB Battery Charging 1.2 Specification charging profiles, which max out a t 1.5A, (c) proprietary protocols that allow for higher than 1.5A charging.

    USB Type-C has a completely different power negotiation scheme compared to USB 2.0/Type-B, and the max charge rate without using active cables and Power Delivery (new standard for negotiation up to 20V@5A=100W), is 3A. There is a Configuration Channel pin that is pulled up by a resistor to indicate max current capability of the charger.

    Regardless, the take-home message is that phones have current limiting circuitry to manage battery charging at the safest level for their batteries, given by a "c" rating. They are ultimately responsible for drawing however much current they can muster from the charger - they can't draw more than the battery charging circuit allows at its peak. Given an ocean of current, they will take only what they need. It is up to the charger to dish out a particular current level if the phone is able to ask for it.

    I wouldn't be worried about the charger hurting the phone as much as I would be about the "3A" charger charging my phone at 500mA, all slow-like. ;-)

    Hope that helps!


    Posted via CB10
    kareem_ruhi likes this.
    06-29-16 10:03 PM
  3. Bla1ze's Avatar
    It generally doesn't matter as long as it meets or exceeds the requirements. The device is protected internally anyway.
    06-29-16 10:08 PM
  4. BlackBurreh's Avatar
    Thank you! I just wanted to play it safe
    06-30-16 08:29 AM
  5. siung6's Avatar
    Maybe it's OK for a short term. In long run, you are hurting your battery due to heat. From time to time I charge mine using the playbook charger which is 2A. It's definitely hotter than the one that come with it.

    Posted via CB10
    06-30-16 12:35 PM

Similar Threads

  1. Replies: 19
    Last Post: 07-11-16, 12:43 AM
  2. Replies: 6
    Last Post: 07-04-16, 12:00 PM
  3. Replies: 1
    Last Post: 06-29-16, 07:04 PM
  4. Replies: 2
    Last Post: 06-29-16, 07:02 PM
  5. Unlocked BlackBerry Passport on Canadian Carriers?
    By CrackBerry Question in forum Other Canadian Carriers
    Replies: 1
    Last Post: 06-29-16, 05:09 PM