Why your charger can't reach the acceptable max current in charging?

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xtarflashlight
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Why your charger can't reach the acceptable max current in charging?

We noticed some customers often asked why their XTAR chargers can’t reach the acceptable max current during charging. For example, VC2 supports 0.5A for 2 channels, but it is always charging with 0.3A; One customer even told his VC2S can only charge one battery at a time when he put two 18650 in. Was the charger broken? Actually, he plugged the VC2S into the the laptop USB port. Because the power supply hasn’t enough output, as the first picture shows below, only one battery can be charged under 1A current, and the other battery can’t be charged due to insufficient power supply.

Besides, there are some other reasons affecting the real charging current. For example, if the charging cable is too thin or too long, there exits high internal resistance loss in the charging cable, and the current through charging cable is not enough. Then, your charger can’t reach the acceptable max current. What’s more, if there are dirty particles, rust or serious friction on the adapter or USB port, which leads to big internal resistance. It may also cause low current charging.

Edited by: xtarflashlight on 01/18/2021 - 00:15
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These bits of information the Xtar throws around the flashlight and battery forums and subreddits are at first glance confusing but once you read them you learn something new.

 

My 2c and a helpful tip for the Xtar team.. Maybe you should preface your topic title with something like Answer to: the question goes here. Or maybe something like FAQ: followed by a question.

 

Let me explain..

 

Since I am new to the flashlight world and a bit new to the batteries and chargers, seing your question in the opening title and seeing your forum username makes me feel like you are asking the community this quesiton. As in you are unsure yourself. Now of course this can only be thought by a beginner.. Anyone who is already deep in this world will know that you are sharing valuable informaiton. Still maybe making putting a FAQ in the title would help mitigate any confusion.

Hope I helped!

wle
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It may be because the cell voltage is at 4.2 or whatever they set the limit to.

More current means more volts, and it cannot be allowed over the 4.2V limit.

The current is limited to what you set, IF the volts are not over 4.2

Otherwise it has to drop the current.

That is what happens at the 2nd stage of charging. Until the current gets to some very small amount like 5 mA.

Why would it do that? One reason, you are charging a cell that is not very discharged, typically if they have over 80% of max capacity, the current cannot be max any more.

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xtarflashlight
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Thanks for your kind suggestions! Wink
And we will keep improving and moving. Also glad the informaiton is helpful to you.