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I'd like to use a boost converter as the primary power supply for a lipo charger. Disregarding the BMS, which will be a separate component, how does a step-up boost converter behave when used as a battery charger?

I'm looking at something like this boost converter, and my system is 28V input, up to 50.4V output (12s lipo). A p-channel switching circuit would switch source (output of converter) to load (battery pack)

A Lipo battery should be charged first at constant current and increasing voltage, followed by constant voltage and decreasing current.

Does something like the above boost converter:

  1. Output maximum current at varied increasing voltage, then decrease current once maximum voltage is reached?
  2. Output maximum current + voltage at all times?
  3. Do something else entirely?

Would a single converter be appropriate, or would the system require one configured for constant current, then switch to another configured for constant voltage?

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  • \$\begingroup\$ Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design. \$\endgroup\$
    – Andy aka
    Aug 12 at 7:51
  • \$\begingroup\$ Welcome to EE.SE. You may wonder why your question is considered as off-topic because dealing with the use of things. You may think that you have asked a proper engineering question. However the engineering task is to look up basic information about boost converters in advance. Such a converter can be modified in many ways, so of course there are some that could accomodate a lipo with extra work. But that wasn't what you asked. Your question asked more less for usage or buying recommendation. \$\endgroup\$
    – Ariser
    Aug 26 at 15:09
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This converter has trimpots for CV,CC,UVP,OCP and indicators Vin on the output UVP, OCP so it behaves exactly how you set it up and may be used to charge batteries but it does not have a shutoff for LiPo or Lithium Ion type batteries usually set to <10% of CC during CV mode.

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    \$\begingroup\$ Which basically means, it's not a lithium charger but a boost converter, so it should not be used as a lithium battery charger. \$\endgroup\$
    – Justme
    Aug 11 at 18:30
  • \$\begingroup\$ More like a lead acid charger unless you add on cutoff circuit with hysteresis on cut-in and protection for dead cell if too high ESR \$\endgroup\$ Aug 11 at 18:40
  • \$\begingroup\$ Thank you both for the feedback. I have pack voltage feedback, and a BMS is in the works for cell voltage feedback. I'd also have current measurement from the boost converter to the pack. Combining the above, I'd actively switch charging on/off. Is that sufficient to safely bulk charge a lipo? \$\endgroup\$
    – Brandon
    Aug 11 at 18:48
  • \$\begingroup\$ The BMS current sensing must be done with no load > cutoff, otherwise no cutoff. \$\endgroup\$ Aug 11 at 18:58
  • \$\begingroup\$ I'm not sure I understand that. Are you saying that with no load on the system, shut off when current is less than minimum current (as you said, typically <10% of CC)? \$\endgroup\$
    – Brandon
    Aug 11 at 19:05

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