Aqualab: Research: Which Kind of Battery?

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Research Topic: Which Battery Will Do?

Last updated:

Overview & Terms
8 March 2012

Single Use
7 January 2016

Rechargeable
10 November 2019

Battery Analyser
23 April 2021

Battery/Charger Shopping
24 April 2021

Original article by Ian Mander, 22 July 2002

Single Use Test
6 November 2007

Rechargeable Test
21 September 2023

Test Procedure
4 June 2011

Button and Coin Cell Shopping
31 July 2021

More Info & Links
29 February 2012

LSD Shootout
7 January 2016

When Battery Testing
Goes Bad –
Consumer Magazine
20 June 2023

Battery Holder Shopping
28 July 2022

On this page: Low self discharge NiMH | High capacity NiMH | Primary batteries | Chargers

Shopping for batteries and chargers

Low self discharge (LSD) cells

Sanyo Eneloop cells are no longer available in New Zealand, but the new rebranded Panasonic Eneloops are. That's not a bad thing in itself, but sadly the Eneloops available in New Zealand are made in China, not Japan. The Japanese made Eneloops look good, but the Chinese made ones appear to be no better than any other LSD batteries. They don't hold as high a voltage under load, and they don't last as many cycles.

Chinese made Eneloops – Panasonic branded – can be bought from PB Technologies (NZ$17.93 for 4). (Link opens a product search for "eneloop".)
Older Sanyo branded cells are still available from some sources, although fake Eneloops have turned up at some shops.

Sadly Dick Smith ~~Electronics~~ has sold out of Eneloops and it's a great pity they didn't recognise their value. Their replacement - a DSE-branded low self discharge cell - are more expensive than PB Tech's Eneloops, and look like a relabeled version of a certain brand of poor quality cell. I don't recommend them. Stick with Eneloops or one of the other top brands. Update Dec 2010: DSE have given up on their house brand and returned to stocking Eneloops! Not the best prices but it's excellent that they have them again. Update Jan 2016: Dick Smith ~~Electronics~~ has gone into receivership and are not honouring gift cards – something I regard as theft.

Note that the second generation Eneloop is rated good for 1,500 cycles (up from 1,000 cycles) and still having 75% of its capacity after three years (85% after 1 year for the first version). Eneloops are widely regarded as having the lowest self discharge amongst all the low self discharge cells available.

GS Yuasa EniTime is a newer arrival on the LSD scene, but GS Yuasa has been around for many years. Users have mostly reported OK results, although their LSD ability isn't the best – initial self discharge (20% loss in the first month) is faster than other LSD cells but settles down to a slower rate after a while.

Higher capacity cells with LSD properties are also available. However, there is a trade off between capacity and other attributes. Cells with the lowest self discharge and the longest cycle lifes are around 2,000-2,100 mAh only. Higher capacity LSD cells have a higher rate of self discharge and do not last as many cycles. For example:

The Sanyo XX AA cell is rated at 2500 mAh, and to have 75% charge after 1 year and last up to 500 cycles. Compare that with the Sanyo Eneloop AA, which is rated at 2000 mAh, and to have 90% charge after 6 months or 75% charge after 3 years and last up to 1500 cycles. For ordinary day to day use I recommend the Eneloop even though it has less capacity.
Rebranded under the Panasonic label (Panasonic bought Sanyo) as the Eneloop Pro, it now claims 85% charge after 1 year.

New Zealand battery retailer Ian Jenkins at Ecobatteries sells Powerex high capacity cells and "precharged" cells with LSD properties.

High capacity NiMH cells (non-LSD)

No high capacity batteries have a particularly long service life, and the advantages and convenience that LSD cells like Eneloops offer along with their very long service life make them much more attractive in my opinion. However, your own needs may mean the higher capacities some cells offer are worth the downsides.

The Maha Powerex brand is available in a 2,700 mAh version at a pretty good price in New Zealand from Ian Jenkins at Ecobatteries. They or the Sanyo 2,700 mAh are probably the best high capacity non-LSD cells available. I recommend Eneloop XX cells instead.

I strongly recommend that people do not buy Energizer NiMH cells. They simply don't have the quality to provide faithful service.

Primary (single use) batteries

GP Digi1 (NiZn) is now sold out from Dick Smith ~~Electronics~~. This is a great shame - they were good batteries that used the NiZn chemistry, which has a slightly higher voltage than zinc-carbon. That extra voltage was sometimes exactly what was needed.

Car alarm remote controls commonly use small 12 volt batteries:

23A, also known as A23, GP23A, MN21, V23GA, ANSI-1181A, 8LR932, 8LR23. These last two names come from the very small alkaline button cells that are used to make the 23A batteries; eight LR932 cells. A 23A battery has about 50-55 mAh capacity and measures 10.3 mm diameter by 28.9 mm long.

27A, also known as A27, GP27A, MN27, L828, 8LR50. A 27A battery has about 22 mAh capacity and measures 7.7 mm diameter by 28 mm long.

A small 6V battery made of four AG13 cell (also known as 76A or LR44 cells) is the 476A or 4LR44.

An alkaline N cell (also called LR1) is not very common. Physically it's about the same size as a 23A battery but with a larger diameter, and only 1.5V.

Chargers

Ecobatteries also sells the excellent Maha MH-C9000 analyser/charger for a good price, and several other models of Maha charger.

International customers may want to try Thomas Distributing, where I bought my original MH-C9000, although their shipping prices for non-US customers are quite high.

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