Rechargable Batteries

JJDLD

Hi,

My bog-standard rechargable AA batteries aren't holding their charge very well anymore, can anybody recommend a good quality replacement? They are mainly used for a short commute (15 mins twice per day) in standard Cateye lights (not super bright ones).

Ta,

JJ.

rickhotrod

Sanyo Eneloop are the best. These are 2000mAh capacity. They are different from normal AA NiMH batteries because they don't discharge quickly, and have a long life if charged properly.

Make sure you use a good battery charger ie. a slow one that charges each battery separately, and has a reliable automatic cutoff when the battery is fully charged. I use a La Crosse BC-700 that was made for the US market. These are now sold in the UK under another name.

It's best to charge these at a rate of 200mA which would take about 12-14 hours to fully charge them from flat. By charging slowly you get maximum battery life, about 500-1000 charge/discharge cycles in the case of these Sanyo Eneloop batteries!

rickhotrod

Some other manufacturers make similar batteries to the Sanyo Eneloop such as Uniross Hybrio, but Eneloops are made in Japan not China!

alfablue

I sort of agree with Rickhotrod about Eneloops, these are best in an device yo use infrequently because they will hold more of your charge, but for a bike light during the winter you need maximum capacity rather than slow self-discharge rate.

I have been using vapextech 2900mah AA's for over a year, they perform very well, are cheap and are delivered next day (£4.95 for 4 delivered from www.vapextech.com). They also make Low Self-Discharge (enleoop type) that work well too. They also sell a smart battery charger that will care for your batteries (the LCD Ultra Fast World Charger) - don't be put off by the ultra fast tag, it is quite slow really!

The BL-700 is a step up and is £26.99 from here.

I use the MAHA Wizard One, which is a bit more pricey.

Don't se a "dumb" charger (one that works on an internal timer, you need one that has temperature and voltage cutouts) or a 15 minute charger. They will cook your batteries.

rickhotrod

JJ only does a short commute. He would be better off with low self-discharge AA batteries that last a lot longer and don't need recharging every week.

The problem with high capacity (eg. over 2100mAh) AA NiMH batteries is that they don't last for anything like the number of charge/discharge cycles that you get with Eneloops and other low self-discharge batteries. Also, some of them such as the Sanyo 2500mAh AA batteries (which i have tested) go completely flat in about 1 week.

I agree with Alfablue about the BL-700. It looks identical to my La Crosse BC-700 and is a good price at GBP26.99 including delivery. The only other battery charger i would consider using is something much more expensive such as the Maha!

GavH

Don't forget that the current cold snap will take its toll on a battery as well. The cold temperature slows down the electrons inside (in essence the very energy inside it) and this in turn reduces the output of the battery.

alfablue

I should have read the OP more carefully, I am used to charging mine every day (Fenix L2D, 4 hour run time). Hybrids would be better for infrequent charging, though I have had no issues with my vapextech batteries running out of steam after over a year of very frequent use, but then I use a very kind charger and I think the batteries are of good quality. For less than £1.25 each they are very good value. Decent standard NiMH batteries (such as my vapextech ones) should not self-discharge more than about 1% per day (hybrids maybe 1% per month) so the Sanyo ones that self discharge in a week are not very encouraging!

Also, the stated capacity is rarely matched by actual performance. I have Powerex 2700mah batteries that actually have a capacity of 2500mah, and are about the best available in respect of matching the stated capacity, whilst my 2900mah vapextechs also only give 2500mah, however the latter are 1/3rd of the cost and seem to have a very long life so they actually represent a better buy.