1

I started wondering how different chemistries are charged and if using a CC/CV power supply to charge them all is a good idea.

So for a li-ion 18650:
1- voltage = 4.1v
2- max current = 1.5A
3- connect battery
4- wait until current falls below 0.1A

Thoughts?

2

Vague memory is Dave Jones did a video of that on Eevblog……back in time someplace.

3

I use a power supply for charging in all my battery test, but it is computer controlled. This means I can simulate charging algorithms correctly.
For CC/CV it works nicely without computer control, as long as you disconnect when the current is low.
For -dv/dt or NiMH/NiCD it do not really work.

Why do you use 4.1V, do you want to get longer lifetime from your batteries?

4

Can you explain charging algorithms a bit? How do the algorithms differ from the setup I described?

Yea longer life.

5

A power supply with current limit will do a fairly good CC/CV, except you manually have to terminate it.

-dv/dt looks for a slight drop in voltage (a few mV) to terminate, this is not possible with a normal power supply

6

Is there any harm in not terminating it? It seems overcharging would be impossible with the 4.1v limit.
And is dv/dt just relevant to NiMH?

7

Yes, more wear on the battery. A few hours extra charge time is not a problem, days is a minor problems, months will add significantly extra wear.

NiMH and NiCd.
Most of my battery reviews contains a charge curve where you can see how I charged the battery.

8

I checked out your site. Wow, good job!
I have a related question, I tried recharging some Energizer alkaline AA batteries a few years back, and some recharged great, and some didn’t recharge at all. Do you have any experience with this?

9

No, but rechargeable alkaline is constructed different than standard alkaline.

10

Yep, I know, I just wanted to see if they would recharge or not :slight_smile:

Thanks for all the info!

11

I use the DPS5020 power supply to charge li-ions on a regular basis but I never leave it unattended or for very long after the charging current has become low.
I think Texas_Ace uses his for this purpose alot too. I have never had a problem charging, checks out to be pretty accurate and follows the proper CV/CC algorithm as HKJ pointed out. Works great for me. :+1: