9 Volt batteries

I'm planing to buy NiMH batteries to replace 9 volt batteries. I'm wondering which would be better 8.4 volt or 9.6 volt?

I've bought those: http://www.gearbest.com/chargers/pp_340887.html (8.4V) in order not to fry my DMM that takes standard 9V primaries.

I bought NiMh because the stock alkalines I buy are no load tested at at 9.6 volts and my Fluke meters have never had a problem over the years. The NiMh charge to 9.25 on my charger.

Vadimax, what kind of meter are you using that is alkaline intolerant?

gnappi said:

I bought NiMh because the stock alkalines I buy are no load tested at at 9.6 volts and my Fluke meters have never had a problem over the years. The NiMh charge to 9.25 on my charger.

Vadimax, what kind of meter are you using that is alkaline intolerant?

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It is not intolerant, I just try to avoid alkalines at all means It is UEi DM393. And I prefer not to feed devices with voltage that exceeds specifications Most likely it will survive, but I'd better not experiment.

DavisonDave said:

I'm planing to buy NiMH batteries to replace 9 volt batteries. I'm wondering which would be better 8.4 volt or 9.6 volt?

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I have started on testing 9V batteries, you can see some different types here: http://lygte-info.dk/review/batteries9V/Common9VIndividualTest UK.html

Thanks HKJ,
I've been looking for rechargeable 9v batteries fro my wireless microphones for a couple of years.
Managed to score 4 x iPower 700mah cells plus a charger. Should see me through a whole show without a change of cells.
I'll report back.
P

Thanks everyone!I have enough alkalines for now so I will wait for HJK to review a few more and for Peter to report back.

Interesting, why don't they make 9V battery, which will consist from 3 LiFe cells in series? it will exactly fit into voltage range, unlike these pseudo-9v lithium rechargeables, which are 7.2 volt actually.

CuriousOne said:

Interesting, why don't they make 9V battery, which will consist from 3 LiFe cells in series? it will exactly fit into voltage range, unlike these pseudo-9v lithium rechargeables, which are 7.2 volt actually.

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Soshine is supposed to have one.

Hm, I've seen it, but I thought it was 2 cell, as others.

CuriousOne said:

Hm, I've seen it, but I thought it was 2 cell, as others.

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Voltage makes it 3 cell: http://www.soshine.com.cn/a627.aspx

HKJ said:

Voltage makes it 3 cell: http://www.soshine.com.cn/a627.aspx

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I am sorry, what about those: http://www.gearbest.com/chargers/pp_340887.html? Is their mAh rating real?

vadimax said:

I am sorry, what about those: http://www.gearbest.com/chargers/pp_340887.html? Is their mAh rating real?

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I do not know yet, but I plan to test them (I expect the mAh is too high).

I've been using the Soshine 650mAh 9V Li-ion batteries in my DMMs and many other devices with great success. If your device can handle the 2S Li-ion voltage range then the 3x capacity increase over NiMh is a huge advantage.

I've now had my iPowerUS 700mah 9v cells for a few weeks now and they certainly do the job I require them for.
I'm using them in Sennheiser wireless microphone body packs, and I'm getting at least 3 hours use out if them.
I did a runtime graph of them when I got them, but it wasn't remarkable one way or the other, the downward curve started to flatten out after about 4 hours and I assumed that the TX circuit had cut out due to low voltage and stopped the test.
However, I did manage to get sound out of the mics after 4 hours, so I was mistaken.
Great cells for my purposes, they look well made and the charger, while all silver and grey plastic, does the job.
After about 3 hours runtime it only takes about an hour to top them up, so I guess there's more juice in them still.
If I have any more thoughts I'll get back.
P
Here's the graph, sorry about the quality, but you get the idea..

You may also consider 9v lithium primary's for things that you don't need often, they are a bit expensive, but they don't leak and last for an eternity

I would not spend $20+ on the iPower 9V li-ion batteries when you can now get Soshine or EBLs for over 5-8 times cheaper. The iPower prices are from the days when they had little competition in the 9V market. Those days are history.

Any update on these yet? Is the advertised capacity legit? Can they be recharged with a regular 9V charger?

7histology said:

Any update on these yet? Is the advertised capacity legit? Can they be recharged with a regular 9V charger?

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If you buy Soshines, they come with a charger.

7histology said:

Any update on these yet? Is the advertised capacity legit? Can they be recharged with a regular 9V charger?

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The capacity ratings on my 15 Soshine and EBL 9V Li-ion batteries were all accurate, i.e. 650mAh, 600mAh. I charge them with true 2S Li-ion CC/CV chargers to maximize life. Some Amazon reviews have claimed that the associated generic 9V chargers are not good quality, but without any technical details to back up that claim (though it is probably likely so). Both can be purchased with or without charger.