Poll: Time to ban alkaline batteries?

[clv101]

With recent developments in NiMH batteries, I'm thinking of the Sanyo's eneloop and similar, isn't it about time we phased out conventional primary cells in favour of the low self discharge NiMH alternative?

Eneloops come charged, keep their charge for years, have low internal resistance so can be discharged and charged quickly and can deliver higher instantaneous currents. They can be recharged 1500 times (1800 with the new models released this week) so the economic savings are dramatic.

Could a mod make this a poll:

Time to ban alkaline batteries?

• No - rechargeables are and will always be rubbish
• Yes - alkalines have poor performance and are wasteful
• Don't know, all too complicated!

 

[clv101]

You need a fourth poll option - "No, alkalines should not be banned as in certain uses they are the best battery to use".

Yeah, I guess that's the case. But I imagine those certain uses are few and that the vast majority of alkalines are used in applications where an eneloop type battery would be a better choice. It's a shame that a minority of niche applications influences negatively the majority.

 

[clv101]

The Problem is NiMH and most recharges like LiPo have poor performance in cold conditions and is the reason I never touch the things for most of my needs such as head torches and avalanche beacons.

Try using rechargeable at -20*C and things can get very dangerous, even life threatening. Alkali batteries are relatively good with cold temperatures.


The other problem with most rechargables is they have less predictive power curves and power output tends to suddenly plummet, Alkaline batteries are much more linear and predictable, so when say a head lamp starts t fade slightly you know you are OK with a regular battery but with a rechargeable it is hard to predict how much longer you wil have usable light but it certainly wont be nearly as long as with an alkaline.

I think both of these points are wrong. Firstly on low temperature performance, eneloops look better:
http://www.eneloop.info/home/performance-details/low-temperature.html

Secondly, on the predictive power curves, NiMH have a flatter response than alkalines, see here:
http://www.eneloop.info/home/performance-details/capacity.html

 

[clv101]

On this topic, what are better Eneloop or Energizer rechargeables? I use (a lot) of Energizer AAs which generally seem good, but not very good on bike lights (they drop off very quickly)

How long do you leave the Energizers on your bike between charges? Even without using them, they will be flat after a while (self discharge). I use eneloops on my bike and they last for several months (~20 min per day, flashing LED, 5 days a week).

 

[clv101]

There is just nothing at a similiar price point to Alkalines at the moment...

How do you mean when considering rechargeables can be reused many hundreds of times. Divide their cost by that and they are considerably cheaper than alkalines?

 

[clv101]

LSD rechargeables can't compete in those applications, when alkalines will sit there for several years without self discharging.

New eneloops claim to retain 70% charge after 5 years - surely that's competitive with alkaline?

 

[clv101]

When its winter you need a battery that will provide the highest consistent voltage because anything less results in failure.

Yeah, but alkalines don't provide that, their voltage falls off faster than good NiMH. Sounds like you'd be better off with a good NiMH.

 

[clv101]

Some things will only work with the full 1.5v, not 1.2v from NiMH batteries.

That would have to be a particularly badly designed product - alkalines don't stay at 1.5v for very much of their lifetime at all. Alkalines voltage vs discharge curves are steeper than NiHM - sure they start of higher, but relatively early in their total life fall below NiMH.

 

[clv101]

However I think it's a bad idea to ban alkaline batteries quite yet, as there are still devices that may not work as well with nimh, or that will likely only use a single battery a year (clocks) etc.

Yeah, I guess there are still some things that need them. How about a minimum price on alkaline such that they are at least same price as NiMH? Dunno what that you be, kinda like a minimum price of £1 a battery or something. Bit like the minimum alcohol price they are talking about in Scotland. Just so there is no price incentive to buy alkaline, they are available if you specifically *need* them, but otherwise buy LSD NiMH.