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Modifying a computer ATX power supply for higher output voltage

Posted on Monday, October 9th, 2017 in hacks by DP

ATXBasedBatteryCharger1

Kerry Wong wrote a post on his blog showing how he modified the 12V rail of a TL494 based ATX power supply to 14.6V for 4S LiFePO4 battery charging:

To charge the 110Ah battery bank I built, I need a power supply that can provide at least 10A at 14.6V. Since I have many old ATX power supplies lying around and the 12V rails of these power supplies are more than capable of providing 10A, I decided to modify one such power supply for using as a 4S LiFePO4 battery charger.

More details at his blog here.

Check out the video after the break.

This entry was posted on Monday, October 9th, 2017 at 3:42 pm and is filed under hacks. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

One Response to “Modifying a computer ATX power supply for higher output voltage”

  1. Blars says:

    This shows how to disable the OVP circuit and increase the output voltage. This does not make a battery charger, you need a constant current rather than foldback current limit, it should turn off when the battery is full, and 14.6V will kill a 4S LiFePO4. 13.8V is much better, 14.2V at most, and 14.4V at what the OVP should be set to.

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