Duracell D size batteries are no longer any good.

[Carl Watts]

After thinking these were the best because I'm still using a pair Duracell D size batteries for testing that had a best install by date of MAR 2005, I have had a battery fail with a best install by date of MAR 2029.



Basically the difference was the construction from when they were made in CANADA to when they are made now as assembled in the U.S.A (does that mean made in China and put into the plastic retail packaging in the USA ?)

Anyway this battery cost me loads of time when I thought the monitor was faulty and then I just happened to notice the negative contact plate was loose, very annoying. Yes that's cardboard on the end and only that centre electrode makes contact with the end plate.

What I have decided to try is the D size battery adapters you can get now that hold 3 standard AA batteries. For AA batteries I'm using Alkaline VARTA and have had no problems with them. D size batteries are really expensive now and moving to AA will also allow me to use my decent Varta Ni-MH 2100mahr AA rechargeable's. These now hold their charge really well over time with their slow self discharge characteristic.

These will catch you out as they measure 1.5V but due to leakage over the electrode there is high resistance and the older PM3 monitor has a high inrush current at start-up when you first fit new batteries and what happens is you just get a blank screen.

[mict450]

Another respected American company bites the dust! But they still charge a premium price for cardboard??!! The damned Chicoms are everywhere!!! Now they're stealing our ground water & operating illegal medical labs culturing highly virulent pathogens in our back yards!! And how was your day?

[Willy.VdW]

I have also seen Duracell batteries leak, but only when completely depleted.
The D-cell in the picture is a different matter, but it can be an exemplary failure.
However, it isn't good for the confidence in and the reputation of Duracell.

[Carl Watts]

I have ordered some D size holders that you fit 3 x AA batteries to, I will post up a review and a link when they arrive.

The only critical thing with these is the overall length, I already have some old ones that take just one AA battery in the centre and they are useless as they are too long and a nightmare to get into the monitor.

Because you can fit in 3 AA batteries in parallel you triple the Ahr capacity so with my 2100mAhr Ni-MH batteries you end up with 6300mAhr capacity.

The Concept 2 monitors use a switching power supply so it really doesn't matter if you have 3V at the start or 2.4V, the battery percentage reading will just change to reflect the lower initial reading.

AA batteries work out at about half the price of D's and any minor leaks have a better chance of being contained in the holder so you can just chuck it away. I spend my life putting new battery terminals in Concept 2 monitors, the leaks can be so bad from D size batteries it easts the terminal away completely until its gone.

[jamesg]

I've a C with PM5 and two Ds that don't last long. There's a USB socket in the PM, can't I just connect a phone supply and forget? Or use a photocell of some type? I never row in the dark. If with no batteries at all, so much the better.

[Carl Watts]

Adapters arrived, they are the perfect overall length and well made.

https://www.aliexpress.com/item/1005004 ... 18021Z02z7

Just get a few of these and move to AA Alkaline batteries or Ni-MH rechargeables. Also in the unlikely event your decent batteries should leak it should get contained in the adapter and you can just toss it in the bin rather than it getting to the monitor battery terminals.

[gvcormac]

Adapters arrived, they are the perfect overall length and well made.

https://www.aliexpress.com/item/1005004 ... 18021Z02z7

Just get a few of these and move to AA Alkaline batteries or Ni-MH rechargeables. Also in the unlikely event your decent batteries should leak it should get contained in the adapter and you can just toss it in the bin rather than it getting to the monitor battery terminals.

Thanks. I ordered a couple. I would've ordered more, but they had free shipping only for 2 or fewer. Backwards, but what can you do?

That said, I just replaced the Ds in my BikeErg for the first time after more than two years and 15 million metres. In twenty years since I got my first Model D I think I've used one pack of 10 D cells among two Model Ds, a SkiErg, and a RowErg.

I've also seen lots of leaky AA cells. So I'm treating this as a novelty/convenience experiment more than cost saving or risk mitigation.

[Willy.VdW]

I've also seen lots of leaky AA cells. So I'm treating this as a novelty/convenience experiment more than cost saving or risk mitigation.

Yes, alkaline AA's leak just as much as the other sizes. As long as leaking batteries don't destroy the monitor,
I think there will be no cost saving at all, comparing the power content of the different models, it seems to
me that D-cells are much cheaper per mah. This may be different using rechargeable batteries.

[gvcormac]

I've also seen lots of leaky AA cells. So I'm treating this as a novelty/convenience experiment more than cost saving or risk mitigation.

Yes, alkaline AA's leak just as much as the other sizes. As long as leaking batteries don't destroy the monitor,
I think there will be no cost saving at all, comparing the power content of the different models, it seems to
me that D-cells are much cheaper per mah. This may be different using rechargeable batteries.

The vaguaries of commodity pricing. AAs are much cheaper than AAAs, and much much cheaper than Ds. And I always
have a drawer-full of both, whereas Ds require special purchase.

[Willy.VdW]

What I found is that D-cells are about twice as expensive as AA's, while the power D-cells
of the same manufacturer have is (or can be) more than 5 times the power of AA's.
I didn't do a major investigation, just took a look at a few eshops.
These were located in the EU, things may be different in other parts of the world.

[nick rockliff]

I have also seen Duracell batteries leak, but only when completely depleted.
The D-cell in the picture is a different matter, but it can be an exemplary failure.
However, it isn't good for the confidence in and the reputation of Duracell.

There are counterfeit Duracell batteries out there just like anything else on the market these days. You can't tell by just looking at them but you soon know when they don't perform how they should.

[gvcormac]

What I found is that D-cells are about twice as expensive as AA's, while the power D-cells
of the same manufacturer have is (or can be) more than 5 times the power of AA's.
I didn't do a major investigation, just took a look at a few eshops.
These were located in the EU, things may be different in other parts of the world.

Interesting. Here in Canada, I can get alkaline AA cells for about $CA 0.35, and D cells cost
more than $CA 2.50. The converter (3 AA to D) costs $2.50.

Let's say that D cells have 6 times as much energy as AA cells (18 vs 3 Ah -- your mileage may
vary). So 3 AAs is about 1/2 of a D cell, at about 1/2 the price.

But in order to get D cells at $2.50, I have to buy a bunch, tying up my money which I could
otherwise invest or enjoy. AAs, on the other hand, have high turnover in my household.

[Willy.VdW]

There are counterfeit Duracell batteries out there just like anything else on the market these days. You can't tell by just looking at them but you soon know when they don't perform how they should.

Sure, but I didn't just compare Duracells.

[Willy.VdW]

Here in Canada, I can get alkaline AA cells for about $CA 0.35, and D cells cost
more than $CA 2.50.

That's more in line with the difference in power.
I don't know why this isn't the case over here in the EU (at least where I looked).
And of course, as Nick rightly remarked, counterfeit is a reality

[Carl Watts]

Overall decent AA cells are better, you can run more options but there are probably more cheap nasty options available as well.

When the D size leak its pretty catastrophic due to the volume of the battery I have seen acid running down the monitor arm.

Having used a few types and having seen 12 years worth of repairs due to bad cells, the best bet are the likes of Energizer and Varta.

Even with Energizer I have had a couple of faulty cells that died prematurely. The move to Chinese manufacture is not always for the best.

Back in the day when Duracell was made in Canada it was the best, not anymore.

The Duracell batteries I have came from the local supermarket so I would be very surprised if they were fake.