Older charger - battery killer or of some use ?

Batteries and Chargers Chargers
1

I was clearing out some oldboxes and found a Vanson V6000 with its power pack. The charging details are

Charge Time (Ni-Mh and Ni-Cad): NiMH batteries charging time:
Battery Type Size Charging Current Battery Capacity Time
NiMH AA

2A 2300 mAh 64 minutes
2A 2200 mAh 61 minutes
2A 2100 mAh 58 minutes
2A 2000 mAh 55 minutes
2A 1800 mAh 50 minutes
2A 1500 mAh 45minutes
2A 1300 mAh 40 minutes

AAA 0.85A 800 mAh 55 minutes
0.85A 750 mAh 52 minutes
0.85A 550 mAh 40 minutes

NiCAD AA 1A 800 mAh 55 minutes
1A 700 mAh 50 minutes
1A 600 mAh 45 minutes
AAA 0.425A 250 mAh 45 minutes

Going from the 2A into Ni-Mh AA and 1A into NiCAD AA. Should I chuck it as a battery killer or are there uses for it?


2

Nothing wrong with 1A or 2A if the end of charge detection works.

The "gentle charge" is largely a myth.

3

that charger should be fine.

4

Vanson...that's a name I haven't heard since 2004!

Although charging AA nimh's at 2A (1C) will not instantly kill them, the heat that's generated at that rate will definitely shorten their life. It's OK to do so once in a while or when you're in a hurry but not charge after charge. Well, at least from my experience.

0.5C is best IMO.

5

Not according to the eneloop datasheet: http://www.eneloop.info/fileadmin/EDITORS/ENELOOP/DATA_SHEETS/HR-3UTGA_data_sheet.pdf

6

I like supporting evidence. It makes statements that much more believable. But who know's if they just want you to kill your battery's faster so you'll buy new ones sooner? Anyways I'm sure someone here has the testing to prove it either way.

7

It says the same on Battery University. And the datasheet is written by engineers, they don't want you to kill their product.

8

What do you think of using the NiCAD 1A for a .5C charge or is there going to be a different charging and termination method than for NiMHD?

I'm thinking of leaving it in the office to use as a fallback charger if something needs topped up.

9

mfm,

What charger are you charging your nimh cells at 1C? Cuz from my experience, the heat kills them.

10

This one: http://www.candlepowerforums.com/vb/showthread.php?253800-Mini-test-Sanyo-MQH02-vs-Sanyo-NC-TGR02-for-AA-Eneloop-charging

11

Charging eneloops at 2A might be fine. I haven't tried but I think I will based on what you've said in that thread. But IDK, it sounds like Sanyo's trying to get more sales. Do they really want us to use these cells for 1500 cycles? ;)

But doing even 1.5A with non-LSD nimh have killed many of my cells. It doesn't kill them instantly. It drastically shortens their cycle life because of the heat. I would get maybe 30 cycles before either their capacity get's cut severely or their current drops. Again, this is from my personal experience..not a website.

12

Now I would back up fishmaniac here because the reason this was stuck away in a box was the NiMHD in 2004/05 came off it rather hot and the batteries lasted about 40 cycles tops. I found some of them in the box and the Maha c9000 rejects them on impedance check, they have been binned.

Anybody know if using the NiCAD option on the Vanson to charge at 1A will be ok, are there diferent termination methods for the two battery types ?

13

Can you show me where battery university recommends only a 1C charge rate? Cool site btw.

14

Maybe it's a great conspiracy by Sanyo, Duracell, Rayovac/Varta etc whose engineers ALL recommend the 1C rate.

Actually the business/marketing departments of Sanyo and others want you to pay top dollars for cheap (to manufacture, that is) chargers that have a low charge rate, contrary to what their own engineers say.

You have a too simplistic view if you think fast charge = hot, slow charge = cool. You can start by looking at the temperature curve of my test at CPF linked above. The problem with slow charging is that termination is not reliable, which will lead to _more_ heat compared to a proper fast charge.

To compare with a 10 year old crappy charger and some old crappy cells isn't relevant.

Nickel-based:
NiCd, NiMH

Charge methods

Constant current, trickle charge at 0.05C, fast charge preferred.
Slow charge = 14h
Rapid charge = 3h
Fast charge = 1h

15

And in another chart, they recommend .5-1C.

So you go ahead and charge at 1C, I'll charge at .5C.

:)