Sanyo Eneloop

[kahheng]

Finally NIMH batteries with very slow self-discharge

http://www.sanyo.co.jp/koho/hypertext4-eng/0511/1101-2e.html

Should be here soon.

 

[Zerstorer]

Well, they're only 2000mAh and I bet they will cost more than the current 2500mAhs. I suspect they might also have compromised on the peak current capability in their bid to lower the self-discharge rates. Who knows...this might be a replacement for Alkalines and may perform similarly...(i.e bad for flash usage). It seems that self-discharge rates are inversely proportional to cell capacities and internal impedance of batteries. The effect has gotten worse and worse from 1850-2100-2300-2500. Personally I feel that the current 2500s self discharge are a design limitation rather than batch problem as all my 2500s are behave that way. Yet, they perform well if you charge them properly.

In the meantime, I'll just conscientiously charge my 2500s everynight before a shoot.

 

[crazypaladin]

This is certainly good news for future batteries. In the meantime, I will use my batteries up to its maximum recycling limit then "upgrade" to this new batteries. How many of us here actually use our batteries to its max before upgrading? Most simply give in to Buy Buy Buy! ;p

 

[kahheng]

Well, they're only 2000mAh and I bet they will cost more than the current 2500mAhs. I suspect they might also have compromised on the peak current capability in their bid to lower the self-discharge rates. Who knows...this might be a replacement for Alkalines and may perform similarly...(i.e bad for flash usage). It seems that self-discharge rates are inversely proportional to cell capacities and internal impedance of batteries. The effect has gotten worse and worse from 1850-2100-2300-2500. Personally I feel that the current 2500s self discharge are a design limitation rather than batch problem as all my 2500s are behave that way. Yet, they perform well if you charge them properly.

In the meantime, I'll just conscientiously charge my 2500s everynight before a shoot.

2000MaH to me is 'useful' capacity benchmark.

Yes, we won't know how good these things are until someone actually tests them.

 

[Xiao_shin]

Seem like interesting product. If given a choice to choose this over 2500 normal sayo, I will get these. Provided price is about the same to the 2500 ones.

When are we expecting to see this new battery?

 

[crazypaladin]

I will still stick to my 2500 mAh and 2100 mAh batteries until they expire then I will buy.

 

[Halfmoon]

Just curious... what is the refresh function for Sony rechargeable batteries?

Seems like this Eneloop do not have this function right?

Can we recharge it even it is not fully discharged?

Any user feedback.. thanks.

 

[lizzy]

Just curious... what is the refresh function for Sony rechargeable batteries?

Seems like this Eneloop do not have this function right?

Can we recharge it even it is not fully discharged?

Any user feedback.. thanks.

think refresh function apply to the charger to discharge the batteries before charging again. some chargers have this functon, some dun. think eneloop can be refreshed like normal rechargables

 

[Halfmoon]

think refresh function apply to the charger to discharge the batteries before charging again. some chargers have this functon, some dun. think eneloop can be refreshed like normal rechargables

What will happen if recharge batt when it is not fully discharged??? Shorter life???

 

[kietgnoel]

What will happen if recharge batt when it is not fully discharged??? Shorter life???

Nothing will happen, generally speaking, as NiMH batteries do not have the memory effect. However, there is a maximum number of times that a battery can be charged before it begins to lose its capacity i.e. the capacity gets lower. IIRC it's 1000 times for the eneloop.

The refresh function has 2 uses. First, it's to condition new batteries. New batteries do not perform at their maximum capacities unless you fully discharge and charge them a few times. There are chargers that do this automatically by comparing the amount of current discharged against the previous one. The cycle is performed until there's no increase in the amount of total charge.

The second use is similar to the first except that you do it after you have been re-charging the batteries several times without discharging them. There is a slight tendency for the batteries to not hold the maximum charge after serveral charging. However, this slight loss is small compared to new batteries.

If you don't have a charger that can automatically do the discharge/charge cycles automatically until the maximum capacity is reached, you can manually do the cycles yourself three times - assuming your charger allows you to discharge the batteries. Usually, three times is enough.

 

[Ola]

Nothing will happen, generally speaking, as NiMH batteries do not have the memory effect. However, there is a maximum number of times that a battery can be charged before it begins to lose its capacity i.e. the capacity gets lower. IIRC it's 1000 times for the eneloop.

The refresh function has 2 uses. First, it's to condition new batteries. New batteries do not perform at their maximum capacities unless you fully discharge and charge them a few times. There are chargers that do this automatically by comparing the amount of current discharged against the previous one. The cycle is performed until there's no increase in the amount of total charge.

The second use is similar to the first except that you do it after you have been re-charging the batteries several times without discharging them. There is a slight tendency for the batteries to not hold the maximum charge after serveral charging. However, this slight loss is small compared to new batteries.

If you don't have a charger that can automatically do the discharge/charge cycles automatically until the maximum capacity is reached, you can manually do the cycles yourself three times - assuming your charger allows you to discharge the batteries. Usually, three times is enough.

I thought it's Li-ion batteries that does not have memory.
NiMH batteries have memory effect and that's why the refresh function is to "remove" or reduce that effect.
Can anyone confirm? :dunno:

 

[micah4]

yes, nimh do hv memory effect but to a much lesser extent than nicads, so it's best to use up the batts b4 charging whereas li ion do not need to...u can charge li ion anytime, any amount of charge left, but do not let it run down to 0%.

btw, eneloops are nimh...and u can use a normal charger for it.

one other point, eneloop is a 'slow' batt, so not good for camera flash - they take a longer time to recycle charge.
it's good for audio/video players like MP3, MP4, torches etc.

capacity wise: 2000mAh is equivalent to around say, a 2500mAh or 2700mAh, so numbers don't really give the real picture.

EDITED: Eneloops are afterall NOT slow batts, as "thw" experienced (read this thread, post #24) - so it's just as good for digicams etc.

 

[yllew]

yes, nimh do hv memory effect but to a much lesser extent than nicads, so it's best to use up the batts b4 charging whereas li ion do not need to...u can charge li ion anytime, any amount of charge left, but do not let it run down to 0%.

btw, eneloops are nimh...and u can use a normal charger for it.

one other point, eneloop is a 'slow' batt, so not good for camera flash - they take a longer time to recycle charge.
it's good for audio/video players like MP3, MP4, torches etc.

capacity wise: 2000mAh is equivalent to around say, a 2500mAh or 2700mAh, so numbers don't really give the real picture.

I heard that Alan Foto is selling 2 for 9 bucks... Can anyone cfm on this??

 

[kietgnoel]

I heard that Alan Foto is selling 2 for 9 bucks... Can anyone cfm on this??

If so, then price has gone down. I bought at $10 for 2 about 1 - 2 mths ago.

 

[kirkchua79]

btw, does anyone knows where can recycle rechargeable batteries??:bsmilie:

 

[Halfmoon]

Thanks for all the feedback....

Guess eneloop is not suitable for camera....

 

[yllew]

Thanks for all the feedback....

Guess eneloop is not suitable for camera....

Juz keep 4 of them as back-up. It never hurts to haf extra that can store for long period of time.

 

[lizzy]

Juz keep 4 of them as back-up. It never hurts to haf extra that can store for long period of time.

yup, got 4 of them as my backup set
think i'll get another 2 for my led torch :bsmilie:

 

[micah4]

There's that uncertainty over whether NIMH batts has memory effects - some experts say NO, some say YES. Whatever it is, it is advisable to follow the brand's advice, if any. For eg. Maha claims to hv a "memory free" technology featured on Maha NiMH batteries, implying that NiMH does hv memory effect but is 'eliminated' by the technology:

Q: What do you mean by "no memory effect" on MAHA NiMH batteries?
Memory is a type of problem that traditional NiCD batteries usually develop. You probably have heard that in order to maintain the life and performance of rechargeable batteries, you have to fully drain the batteries before recharging them. Thanks to "memory free" technology featured on Maha NiMH batteries, you can charge them anytime you wish, regardless if the batteries are fully drained or not.

Q: How often should I condition my batteries?
Generally speaking, NiMH batteries do not suffer from the "memory effect" and thus do not require conditioning. Nevertheless, to ensure top performance, conditioning is recommended at once for every ten charges. For Nickel Cadmium (NiCD) batteries, conditioning is recommended every time you charge your batteries.
[Unquote].

Source:- "http://www.thomas-distributing.com/maha-educate-batteries.htm"

Here's an extract from source: "http://www.batteryuniversity.com/partone-4.htm"

The nickel-metal-hydride battery

Nickel-metal hydride is less durable than nickel-cadmium. Cycling under heavy load and storage at high temperature reduces the service life. nickel-metal hydride suffers from high self-discharge, which is higher than that of nickel-cadmium.

Nickel-metal hydride has been replacing nickel-cadmium in markets such as wireless communications and mobile computing. Experts agree that nickel-metal hydride has greatly improved over the years, but limitations remain. Most shortcomings are native to the nickel-based technology and are shared with nickel-cadmium. It is widely accepted that nickel-metal hydride is an interim step to lithium-based battery technology.

Here is a summary of the advantages and limitations of nickel-metal hydride batteries.

Advantages

* 30-40% higher capacity than standard nickel-cadmium. Nickel-metal-hydride has potential for yet higher energy densities.
* Less prone to memory than nickel-cadmium - fewer exercise cycles are required.
* Simple storage and transportation - transport is not subject to regulatory control.
* Environmentally friendly - contains only mild toxins; profitable for recycling.

Limitations

* Limited service life - the performance starts to deteriorate after 200-300 cycles if repeatedly deeply cycled.
* Relatively short storage of three years. Cool temperature and a partial charge slows aging.
* Limited discharge current - although nickel-metal-hydride is capable of delivering high discharge currents, heavy load reduces the battery's cycle life.
* More complex charge algorithm needed - nickel-metal-hydride generates more heat during charge and requires slightly longer charge times than nickel-cadmium. Trickle charge settings are critical because the battery cannot absorb overcharge.
* High self-discharge - typically 50% higher than nickel-cadmium.
* Performance degrades if stored at elevated temperatures - nickel-metal-hydride should be stored in a cool place at 40% state-of-charge.
* High maintenance - nickel-metal hydride requires regular full discharge to prevent crystalline formation. nickel-cadmium should be exercised once a month, nickel-metal-hydride once in every 3 months.
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[ekardo]

anyone using eneloop for camera and experience the slow performance?

thinking of getting 8 and disposing my sanyo 2700...useless crap..