LSD longterm not so good?

[JohnR66]

I have some RayoVac Hybrids that will be 3 years old in Jan 2010. I use them in a radio. The radio has a digital interface and shuts off when batteries are too weak. Voltage from the cells are around 1.1 volts when I remove them from the radio. I charge them in a smart charger that chargers at 500ma. It has independent channels and seems to function okay.

To get to the point, These batteries seem to not to last very long per charge now. I would expect them to last at least a few houndred charges. I doubt I have charged them anymore than 40-45 times.

I can send these to someone in the US with one of those fancy analytical chargers to check them with. I'd be interested to see their real capacity.

These Hybrids have a white top which I think were used in the earlier ones and has "TYS S" code printed on the side.

Thanks, John

 

[Marduke]

Well, I'm sure using the improper charge rate is not ideal... (assuming AA's)

 

[Mr Happy]

Rayovac Hybrids are not eneloops. Your title suggests a problem with LSD cells in general, which is not something you can extrapolate from just one brand.

 

[Bullzeyebill]

Please do some searching. For example, use google, cpf only, at the top of every CPF page, and write in Rayovac Hybrids. You will see many, many threads dealing with Rayovac Hybrids. People will contribute to this thread, but you will gain more info by searching.

Bill

 

[davidt1]

3 years are not bad. My Rayovac Hybrids lasted something like a year. They are definitely not Eneloops.

 

[Black Rose]

Is that 1.1v loaded or unloaded?

As Marduke noted, 500 mA is below the recommended charge rate for 2100 mAh AA cells.

If you've got a friend with a more advanced charger (BC-900/9009 or C9000), get them to run a few cycles at the recommended charge rate and see if they come back.

I've had issues with non-LSD NiMh cells that didn't last long due to my pre-CPF charging regimen, which was similar to yours.

I've been using Hybrid AA cells for close to 2 years in radios, scanners, and Wii remotes and they are still going strong.
They have only been charged/maintained with Maha chargers (C800S & C9000) @ 1000 mA.

I have a lot more Eneloops and Duraloops than Hybrids, but the Hybrids are still working fine so far (knock on simulated wood).

 

[TakeTheActive]

I have some RayoVac Hybrids that will be 3 years old in Jan 2010. I use them in a radio. The radio has a digital interface and shuts off when batteries are too weak. Voltage from the cells are around 1.1 volts when I remove them from the radio. I charge them in a smart charger that chargers at 500ma. It has independent channels and seems to function okay.

To get to the point, These batteries seem to not to last very long per charge now. I would expect them to last at least a few houndred charges. I doubt I have charged them anymore than 40-45 times...

"Open Circuit" voltage measurements on NiMh/NiCd cells are rather meaningless. Put a lightbulb or a resistor across the cell drawing at least 0.2C and THEN measure the voltage.

CLICK on my Sig Line LINK and read the sections related to:

• Cell Recovery
  .
• Theory
  .
• Internal Resistance
  .
• Crystals

Your cells probably need a "Break-In". Possibly a few DEEP DISCHARGES followed by some 0.1C 16 Hour CHARGES and they may come back to 'better' performance.

• How many CELLs are involved?
  .
• Do you LABEL them?
  .
• Do you have SPARES?
  .
• What is the MAKE/MODEL of your charger?
  .
• What is the mAh Capacity of your cells?

TIME your charge cycles.

You realize that just ONE *CRAP* cell (in a SERIES circuit) can possibly shut the device (radio) down. :thinking:

IMHO :tinfoil: , (practically) *EVERYONE* needs to own a "SMART Charger / Analyzer" in order to determine WHICH cell (out of the 2 or 4 or 6 or 8...) that you've loaded into your device is UNDERPERFORMING. NiMH/NiCD cells differ from alkalines - while alkalines drop voltage gradually (a slope), NiMH/NiCD cells HOLD their voltage (called the 'plateau') and then they FALL OFF THE CLIFF!

Read / Learn / Come back with more questions...

 

[JohnR66]

Thanks for the links. I did read some stuff beforehand but did not get the full story. I always did keep them paired by marking them in some way. I always ran them in a device until the device shut down even though there may be some charge left. I didn't know that 500ma would be too low to charge an AA cell.

Looks like I really need an advanced charger that can condition and analyze the cells. These aren't cheap, so I'll have to add it to my list of toys to save for. It makes sense to buy another 4 pack for $10 and use them for another 3 years. I use this radio every day as it has an alarm to wake me. feeding it Alkalines would get costly.

I'm aware of Eneloops that are superior. I was lucky enough to snag a couple packs of "duraloops" (white top) for $6.50 at Target last month. I use them in my camera. I keep the old Hybrids around for radios and flashlights.

 

[mikekoz]

From what I understand...it causes flashbacks later on as you get older.......wait....you mean LSD BATTERIES!!!!!:nana::nana::nana:

 

[Bones]

...

As Marduke noted, 500 mA is below the recommended charge rate for 2100 mAh AA cells.
...

I remain baffled by inferences that slower charge rates will inherently lead to under-performing cells and reduced cycle life.

As long the charger utilizing these rates terminates when it should, how is the harm inflicted?

 

[Marduke]

I remain baffled by inferences that slower charge rates will inherently lead to under-performing cells and reduced cycle life.

As long the charger utilizing these rates terminates when it should, how is the harm inflicted?

The key phrase is "if it terminates properly". The termination signal below 0.5C is not very prominant. Only a select few chargers can reliably pick up termination below 0.5C, and only with cells in reasonably good shape.

Throw in a marginal cell or a "typical" charger (that charges below 0.5C) and you can cook your cells from a missed termination.

 

[Bones]

The key phrase is "if it terminates properly". The termination signal below 0.5C is not very prominant. Only a select few chargers can reliably pick up termination below 0.5C, and only with cells in reasonably good shape.

Throw in a marginal cell or a "typical" charger (that charges below 0.5C) and you can cook your cells from a missed termination.

Okay, I get the termination signal issue, but as you have noted, there are chargers such as the Sanyo MQN05 and the Duracell CF23 that still appear to be able to terminate reliably even with somewhat marginal cells. In fact, even the lowly Sanyo MQN06 appears to be able to terminate reliably, albeit while charging in series. I also have both Sanyo USB powered chargers, and they too can terminate reliably, even with a quartet of Energizer AAA cells that baffle both my original and most recent edition of the MH-C9000 charging at a full 1C.

It's my distinct impression that our perception that charging at less than .5C will inevitably lead to missed terminations is driven primarily from our experience with multiple-rate chargers such as the MH-C9000 and BC-900, and I speculate that it's caused by a termination algorithm that's compromised to accommodate several different charge rates. Conversely, the single-rate chargers can be tweaked ad-nauseum to terminate solely on the specific rate they employ.

 

[JohnR66]

The charger I use is Q2 Quest Charger. One the bottom: AS.PINE model A05AA21AA

I notice the batteries are around body temp (98 Deg F) during charge. Near the end of cycle I notice the temp rises and at that point I know that within a few minutes the red light turns green and it beeps indicating end of charge. Nonscientific, but it seems to terminate okay.

 

[mikekoz]

Sorry for the corny humor I posted earlier!! I use hybrid cells also made by Rayovac and Kodak. Some I have had for a few years and they are still going strong. I have no idea how many times I have charged them, but I am not using an expensive charger. My charger was about $25-30.00 and is made by Radio Shack. It is prob about 12 years old, charges 8 AA's at once in about 2 hours, and I am pretty sure it is a smart charger. If your batteries have only been charges bout 45-50 times, one or more of them may be bad. I think these batteries are supposed to be able to be charged about 1000 times. Somebody will correct me if I am wrong!:huh:

 

[TakeTheActive]

Thanks for the links. I did read some stuff beforehand but did not get the full story...

...Looks like I really need an advanced charger that can condition and analyze the cells...

You didn't answer any of my questions (Post #7). BUT, I'd wager that you could put some 'new life' into your '3-year-old' cells with:

1. A couple of 1N4001 diodes
2. A couple of 'various ohm / various watt' resistors
3. A DUMB, un-timed ~150-200mA charger
4. Some personal 'Time & Effort' reading my Sig Line LINKs

...It makes sense to buy another 4 pack for $10 and use them for another 3 years. I use this radio every day as it has an alarm to wake me. feeding it Alkalines would get costly...

If you only have *FOUR* cells that you're concerned with *AND* they lasted you 3 years, figuring your ROI, just KEEP DOING WHAT YOU'RE DOING!