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Battery charger testing

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rakeshm55:
I have a lithium ion battery charger used to charge a 14.4V battery pack. I want to test it's performance so hooked it up to an electronic load in CV mode. I was expecting charger to enter Into CC mode for charging.
What I observed was error indication by charger.As I understand charger is using LM2677 for charging battery. It is capable of charging li ion battery pack to 15V max.

How to test battery charger using a test equipment.?? Is there any standard battery charger circuit for LM2677

malagas_on_fire:
What about some battery pack made of super capacitors to get faster results? Eg:

https://www.hackster.io/janost/super-capacitor-power-bank-e2f7cc

https://www.instructables.com/id/The-Forever-Rechargeable-VARIABLE-Super-Capacitor-/

ledtester:

--- Quote from: rakeshm55 on August 22, 2019, 07:05:06 pm ---How to test battery charger using a test equipment.??

--- End quote ---
I have a feeling a battery is the best way to test a battery charger.


--- Quote ---Is there any standard battery charger circuit for LM2677

--- End quote ---

You could try adapting this LM2596 charger circuit:

https://www.mpja.com/download/31562ps.pdf


radiolistener:
14.4V very strange voltage.

Usual Li-Ion cell has nominal voltage 3.7 V. It should be charged max to 4.2 ± 0.05 V. Military grade should use max 3.92 V instead of 4.2 V. So, your charger should stop charge when voltage on one cell of Li-Ion accumulator is close to 4.2 V but should not exceed this voltage even for 0.05 V!

Since you have battery pack, it looks like your battery has 4 cells. So, the charger should use 4.2 * 4 = 16.8 V limit.

So, just connect the battery and make sure that your charger apply charging voltage to the battery and stops to charge it below 16.8 V.

MosherIV:
Hi. Due to the growing market for LiIon batteries, you can now get battery simulators, a combined psu and electronic load.
There are also electronic loads that have a battery simulator mode now.

Standard electronic loads will not do the job because a battery changes as it charges. The terminal voltage rises.
In order to use an electronic load to simulate a battery, it must be controlled externally and made to simulate a battery.
Not sure CV mode is correct on the EL. The charger will be in CC mode which means it will vary the voltage to get the current but the EL will vary the resistance to try and maintain the voltage - in other words they are fighting each other.

The charger is probably checking there is sufficient battery voltage before starting the charge. The EL will not have any voltage, it is not a voltage source.

Edit: 14.4V good point. 3s is 12V and 4s is 16V
I have the same problem with converting a 14.4V NiCad battery drill to LiIon.
Sounds like the battery is NiCad or NickelMetalHydride
Not advisable to used LiIon charger for different chemistry unless it supports them

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