Best rechargeables for Jetbook?

[Ken Maltby]

The Sanyo Eneloops appear to have an almost cult following, and you are subject to a
violent responce if you don't proclaim these, admittedly good, made in Japan batteries,
as the greatest batteries made. Or if you cast any doubt on their ability to dramatically
out perform all other batteries.

As to GA Russell's question; my on going testing -IN THE JBL- of the Low Self Discharge
2500mAh "eMax+" and the regular rechargable 2300mAh Energizer; includes the
following:
The "eMax+" were removed from the charger after a >14hr "Overnight" charge
then were installed in the JBL 9days 6hr 20min. latter.

The Energizer (non-LSD) were given a 2hr charge and
then were installed in the JBL 24days 16hrs latter.

The "eMax" LSD fell from the four bar power level to 3 bars at the 6hrs of use point.

The Energizer fell from the four bar power level to 3 bars at 9hrs 5mins. of use.

I am still testing the relative performance, under my normal use pattern, in the JBL,
of the Energizers (still on 3bars at >20hrs).

I would have to say, so far, that the Low Self Discharge characteristic is showing no
benefit, at this point. Also that the normal rechargable, even though rated lower than
the LSD rechargable, is showing no drop in performance (relative to the LSD) despite
the 24.5 days of shelf time.

Luck;
Ken

[GA Russell]

Thanks Ken. I guess there is always going to be a little bit of discharge.

[jj2me]

Originally Posted by GA Russell

I've been recharging my NiMH Duracells three days before I expect to need them. May I assume that they lose close to nothing during that three day period?

Yes, close to nothing.

I'm now going to use the following rule of thumb:

~0.9%/day self-discharge for traditional NiMH
~0.2%/day self-discharge for LSD NiMH

[EDIT: Caveat: That "rule of thumb" is just mine, derived from the figures in my previous post. It's not like it's a well-documented rule of thumb.]

[jj2me]

Originally Posted by Ken Maltby

The Sanyo Eneloops appear to have an almost cult following, and you are subject to a
violent responce if you don't proclaim these, admittedly good, made in Japan batteries,
as the greatest batteries made. Or if you cast any doubt on their ability to dramatically
out perform all other batteries.

As to GA Russell's question; my on going testing -IN THE JBL- of the Low Self Discharge
2500mAh "eMax+" and the regular rechargable 2300mAh Energizer; includes the
following:

Not sure who you think is a cult follower. I've never noticed any cult following--it's simply an improved technology of NiMH batteries. Maybe you're seeing people simplifying recommendations, saying to just go with the newer technology? That's understandable as a simplification. It's also understandable if you don't like LSDs' benefits compared to their drawbacks, and want to explore further the differences.

The well-understood benefit is a lower self-discharge rate, which is most helpful in a) sporadic-use devices (i.e., that don't get their battery power depleted quickly), and b) keeping charged spare batteries. Current drawbacks are a higher price and lower capacity than traditional NiMHs.

Do you really think you should claim your Ansmann test is measuring a true LSD?

1. the major manufacturers have not yet been able to make a 2500 mAH true LSD;
2. earlier in this thread chainring directed you to a thread where a distributor called these Ansmann batteries a hybrid between true LSD and traditionals.
3. your test results so far don't indicate any low self-discharge capabilities with the Ansmanns, contradicting all other tests of true LSD (2100 mAH) NiMHs from major brands like Eneloop, Rayovac, and Sony.

If I had a jetBook Lite, I would use either type of NiMH, because this is a device where you use up the charge relatively quickly (one to three weeks). Even the spare batteries won't lose much. If I had to go out and buy a set of rechargeable NiMHs, I'd probably buy true LSDs, because of their versatility in other uses, for example, as spares or in flashlights and clocks.

[Ken Maltby]

Perhaps the issue of self discharge requires more than a month of shelf time, to rear its
ugly head? If so, I don't see how it impacts most users of the JBL.

What might be a more interesting comparision would be the after charging shelf life of the LSD Rechargables vs. Primary Batteries shelf life. Which would be better to have if I needed to have "charged" batteries after many months of storage? Of special interest
might be the Lithium Primary Batteries.

As it is, if I can get the 24 days after charging shelf life from the non-LSD ubiquitous
Energizers and see no problem, I don't see the need for the "LSD" feature, for use with
the JBL. If I should somehow manage to leave a set of the batteries unused for a number of months, so that the self discharge effect mattered, I could probably stand to
wait the 2hr to charge them.

(The Energizers are at >24hrs use time and still 3bars, I expect the end soon.)

Luck;
Ken

[jj2me]

Originally Posted by Ken Maltby

Perhaps the issue of self discharge requires more than a month of shelf time, to rear its
ugly head?

Why not three weeks, like I calculated in yesterday's post, or "weeks," like Wikipedia says?

Originally Posted by Ken Maltby

If so, I don't see how it impacts most users of the JBL.

If you only use that set of AA NiMH batteries for the sole use in a JBL, then yes, no need to consider further. But if you rotate a set of such batteries in other devices, then it's not just a JBL issue. And you probably will, at least eventually, because in the year 2015, you'll still have perfectly fine NiMH batteries with 400 charge cycles left, but likely have given up your JBL.

Originally Posted by Ken Maltby

What might be a more interesting comparision would be the after charging shelf life of the LSD Rechargables vs. Primary Batteries shelf life. Which would be better to have if I needed to have "charged" batteries after many months of storage? Of special interest
might be the Lithium Primary Batteries.

No rechargeable, of any type that I'm aware of, can compare to the shelf life of a non-rechargeables.

[Ken Maltby]

Removed from charger (2hr charge) 14 Mar 1000hr

24 days 16hrs of shelf time later:

Installed 08 Apr 0140hr (showing full charge in JBL)

at the 9hr 5min of reading point dropped to three bars

at the 24hr 07min of reading point dropped to two bars

at the 24hr 27min of reading point the low battery warning appeared
[ending the test run] on 18 Apr (batteries test at 1V and in the edge
of the "Good" in the 1.5v battery test function)

SO; 24hr and 27min of actual use time and 10 days 18hrs 20min. of
standby time.

---------------------------

The next run will be the first test run of the PowerGenex 1.6v NiZn
batteries removed from their charger 0050hrs 09 Apr .
Installed into the JBL 18 Apr 2050hrs.
(9days 20hrs shelf time)

Luck;
Ken

[GhostHawk]

Thanks for the update Ken! Salute Karma headed your way sir.

[DoctorOhh]

Looking forward to your next set of numbers.

Thanks!

[Ken Maltby]

Darn it! One of the PowerGenex 1.6v NiZn batteries went bad at around the 18hr point.
All the rest are reading around 1.5v, but the one bad battery is reading ~ .5v. This
invalidates this run and I'll have to start it over. They were doing amazingly well with
the JBL reading 4 bars at 17hrs of use. I'll have to use the set that shipped in the
charger (even though the instructions say that you should not leave the batteries in
the charger when they are not charging) They show a full charge and I couldn't get
the charger to charge them prior to use. So I'm going to have to try and run them
down some and then try and do a full charge, using the charger, for a proper test run.

Sorry for the delay.

Luck;
Ken

[GhostHawk]

Thanks for trying. Will be watching for results on the new run.

[aagstn]

Wow, really cool stats on the batteries. I have a nice stockpile of Eneloops already so I'm good to go when my Jetbook Lite arrives.

[Ken Maltby]

OK, I've started a new test run of the Powergenix NiZn 1.6v batteries.

I originally had two sets of four AA NiZn batteries one set came installed in the charger
and another set I ordered at the same time. The first set I tried ended its run at 18hrs
27min.s of use, with one battery reading 0.5v and the other three reading ~1.5v. I marked the battery at 0.5v, as bad.

I recharged that set, including the bad one, and they all charged normally and all read
at full charge (>1.5v) after removal from the charger.

The set that shipped with the charger was still charged enough that the charger would
not charge them, so I used that set in the JBL until it dropped to three bars, then removed the batteries - again one of those had dropped to 0.5v. I again recharged this
set including this bad one, as well. They also read all at full charge.

For this test run I replaced the bad battery from one set with a good one from the
other set, so they are all batteries that had not failed in previous use. If it should turn
out that this test run ends with one of these discharged to 0.5v and the others still
good, then I would begin to suspect that somehow the JBL is draining one of these cells
in preference to all the others. If not then these batteries seem to have a 25% failure
rate, on first use.

I hope this can be worked out, because as it was, I got 18.5hrs use and still had three
batteries that appeared to have hardly any drainage, at all. I hope that it's just bad luck with those two batteries and that the "good" ones stand up to a lot of use.

Luck;
Ken

[Ken Maltby]

Removed from charger (8hr charge) 26 Apr

A few hours of shelf time later:

Installed 27 Apr 0110hr (showing full charge in JBL)

at the 8hr 5min of reading point dropped to three bars

at the 20hr 50min of reading point dropped to two bars

at the 21hr 18min of reading point the low battery warning appeared
[ending the test run] on 30 Apr (3 batteries test at ~1V and 1 battery
tested as dead, not moving the needle at all.)

SO; 21hr and 18min of actual use time and 3 days 7hrs 3min. of
standby time.

--------------------

I can't explain the odd results I keep getting with these batteries,
it's as if they are not able to evenly discharge in use. I am tempted
to think that they are aware of my distaste for the whole "Eco-
Friendly" concept. It may be that the "Dead" battery will charge back
up like the 0.5v "Bad" batteries did from my prior efforts, at some point
I will try the bad batteries in a separate test run.

I'll try and put together a set of 4 batteries that have never "failed"
from the remaining NiZn batteries, for a second test run, after the
second runs of the other Batteries under test.

Luck;
Ken

[GhostHawk]

Talk nice to em Ken!