Battery ?

I guess It all comes down to how much to how much you want to spend for accuracy and your needs.

With the cheap DMM, can you measure house current 110v and 220v?

See here: Review of UNI-T UT61E

Usual yes, but it is more dangerous.

In your review, What do you mean by current ranges are bad at low voltage use and they have to high burden voltage? Are batteries considered low voltage with NiMh being at 1.2v and Li-Ion at 3.7v?

Yes, batteries are low voltage. Depending on range you can loose up to 1.1 volt over the meter.

Is it because of the leads are junk or is it just the meter? Can a calibration fix the lost of voltage?

I will not call the meter junk, but it is not always good at measuring current. Calibration cannot fix it, using a higher range and loosing some digits is often a solution.

@ HKJ I was calling the test leads junk and not the meter (I worded it wrong). Is having the extra digits in a meter worth it or is that just in the UT61E model? Do you have any more reviews on DMM on your website?

If you need extra digit or not depends on you and what you do. You usual also get considerable better precision with one digit extra. I like the resolution and have meters up to 7½ digits.
One example on resolution:

A cheap meter says a LiIon has 4.18V specification for meter says 0.5%+2, this means voltage is betwen 4.14 and 4.22 volt.
A better meter says a LiIon has 4.183V specification for meter says 0.5%+2, this means voltage is betwen 4.16 and 4.21 volt.
A better meter says a LiIon has 4.183V specification for meter says 0.1%+2, this means voltage is betwen 4.18 and 4.19 volt.

I have been meaning to do more DMM reviews, but never had time to do it.

Hi everyone,
I want to share with you my experience with reconditioning batteries method which I find on Candle Power Forums.

Few days ago I was interesting of reconditioning rechargeable batteries after watching the video on “”ezbatteries site”:http://ezbatteriesreconditioning.com Of course I was very skeptical because It looked too good for me. I could not believe that it could be possible, so I decided to check it. I was looking for movies before “how to recondition batteries” on youtube and other websites but I didn’t find any specific information in this topic. Especially when it comes to recondition rechargeable batteries (aa, 18650 etc.) or laptop batteries. I tried before only with car batteries and method turned out to be successful (epsom salt method - is easy to find on youtube). I had to take a risk and spend 47$ for this “extra” guide and… It really works :slight_smile:
Actually I have about 10 reconditioned batteries and I’m in the process of testing performance of this batteries. So far it looks pretty good. I use deep cycle batteries (lead-acid) in my workshop from 2008 and I also wants to test this method for these batteries in the coming days. Soon will share the information about reconditioning this type of batteries. Does anyone have any experience with battery reconditioning? I will gladly share the informations.

A few very expensive meters do it another way and mostly eliminates burden voltage (This does not make them perfect ammeters).

The best way to get a low burden voltage is a DMM with fairly high resolution and then use a higher range than required, like you say. Knowing the DMM and when to do that select next range is very useful.

Many DMM’s have 3 current shuts:
uA shunt, mA shunt and 10A shunt, matching the settings on the switch. This means the low uA and low mA range has low burden voltage, but the high uA and high mA (often x000uA and x00mA ranges) has high burden voltage. To get low burden voltage select next higher range for these two ranges when using more than 10% of the range.
I.e. when measuring 0.5mA (500uA), do not do it on the uA range, but select the mA range.
Same with 50mA and up, use the 10A range (Most meters are missing a xA (like 2A) range).
A meter like UT61E with a 22000 reading will give a acceptable resolution in most cases.

In total there are 4 options for measuring current:

  1. A normal ammeter (DMM in current range)
  2. A external shunt with a DMM, this way the best shunt value can be used.
  3. A feedback ammeter, but it is way to expensive for most people.
  4. A clamp meter, they are usual not good at low current and precision is not as good as the above solution.

1) is the worst in burden voltage and 4) is the best (In some situation 3) can be slightly better).
Except 3) all can be found at hobby friendly prices.

It is not that long time ago (Sometime last year) there was some talk and also a group buy of a cheap UNI-T clamp meter (UT210E) that could measure DC on the clamp. With carefully zeroing it could work down to a few mA. Big Clive is using the same clamp meter in his recent videos.

Correct you are HKJ. :+1: Here is a link to the thread about the UNI-T Clamp Meter (UT210E)

Thanks for the replies!

Amen to that…. :+1:
HKJ has forgotten more than I know or will most likely ever know.
Same goes for gauss.

Thanks for sharing & trying to help us mere mortals out. And I say that in all seriousness……. :+1:
.
:slight_smile:

Can Eneloops be stored in the kitchen with heat from the oven or does it has to be stored in a cooler place?

AFAIAC it makes little difference as long as it is not in the hot oven or on top of the hot stove. :smiley:

I have had them stored in truck glove box or under seat for years, thru cold
of winter (0 F) , hot of summer (120 + F inside truck), and anything in between. I can tell no real world or use difference. They all still hold rated capacity & work just fine.

I am sure there is a “text book” answer that would be different and give semi strict parameters of use & storage…. but for me, the real world route is & has been working just fine.

My .02 …. ymmv. :slight_smile:

Is battery reconditioning discharge and charge of a battery? How long does it take to discharge and charge (example) Eneloop AA?

It depends on the charger used and the charge/discharge parameters set.
I am going from memory here, but I think using my Lii 500 charging at 1000 ma is roughly 2 hours. It then automatically chooses the discharge rate of 500 ma (for that charge rate) so that is about another 4 hours. So roughly 6 hours for a reconditioning or capacity measurement cycle with the Lii 500 for an Eneloop AA.
But bare in mind you will just be doing this every now and them most likely……

With the Maha MH-C9000 it can be done much faster, if one so desires; because of the adjustable charging rate from 0.2 to 2.0A and discharging rate from 0.1A to 1.0A. But it also costs about 2.5 times as much as the Lii 500.

I have both chargers but actually pretty much have just gone to using the Lii 500. I am usually in no rush and just start it up and go to bed and when I awake it is finished doing it’s thing. :slight_smile:

Here is a link to HKJ’s review of the Lii 500……
http://lygte-info.dk/review/Review%20Charger%20LiitoKala%20Lii-500%20UK.html

Here is a link to HKJ’s review of the MAHA MH-C900 ……
http://lygte-info.dk/review/Review%20Charger%20Powerex%20MH-C9000%20UK.html

Keep in mind the Lii 500 will also work with rechargeable LiIon cells… the C-9000 will not.

Also, please note: These are the only two that I am gonna mention. There is a long list of other chargers out there that some will say are better. That may or may not be true. Personally, I have come to the point that I do not care. This is what works for me… when & if it quits working for me I’ll regroup. Till them I am content with using what I have.

To be honest the endless search for something better, the latest & greatest; is largely just a bunch of BS to me. Untold amount of dollars wasted in search of the holy grail…… :person_facepalming: … To me it has & is becoming just plain out stupid to continue this nonsense.

If something works, use it and be happy is my new motto. SURE, if something comes along that is new technology &/or clearly better… I’ll sure give it a look. But otherwise… no thank you. :slight_smile: I’d rather spend my time using what I have than using the time in the endless search for something “better”.

Off my soapbox now…… good luck. :slight_smile: