New fangled battery woes!

Harveytile

What the hell is up with "hybrid" recharchable batteries? :shock:

My Cateye front light (HL-EL 510) uses 4 AA batteries. I've been using standard alkaline batteries but decided rechargables are the way forward. Pffft :roll: The fekking things say AA on the box but are ever so much bigger than std AAs! What gives?

Needles to say I have managed to get the rechargables partly in only to find the light will not do up or come apart.

Until I tried a bit harder...I now have four separate parts where I should have two. .

Anyone else have similar problems with rechargables or am I just a div? :oops:

deptfordmarmoset

I got a rear light that I still haven't tried to put rechargeables into - and I'm dreading the ''it won't fit' moment. But it has been the topic of gah threads on here before, so it's not just you - the solution where there is a solution - is often using a very fine file to make room for them.

TuckerUK

An AA is an AA, all the same size. What brand of rechargeables?

alfablue

TuckerUK wrote:

An AA is an AA, all the same size. What brand of rechargeables?

Unfortunately they are not all the same, the AA standard can be 13.5–14.5mm x 50.5mm, some lights fit the smaller but not the larger (or fit very tightly).

Headhuunter

alfablue wrote:

TuckerUK wrote:

An AA is an AA, all the same size. What brand of rechargeables?

Unfortunately they are not all the same, the AA standard can be 13.5–14.5mm x 50.5mm, some lights fit the smaller but not the larger (or fit very tightly).

Yep, definitely, come rechargeables are bigger than standard batts. I've had probs in the past too.

TuckerUK

Some AAs come with adapters to enable their use in C cell electronics? Might that be the issue?

TuckerUK

...if not, I wonder if this problem is peculiar to cycle lights, cycle lights from one country, or even just one brand.

I use LOTS of AAs, (camera, camera flashes, off camera flashes, radio control vehicles, spares for all) of various flavours, and over the past thirty years of my adult life must have consumed hundreds (possibly thousands), including expired rechargeables. I've never had a AA that didn't fit where an AA should (presumable because allowance was made in the equipment to take the diameter variations).

Someone should do an expose on this, what's a standard if it isn't standard?

OP should return light as 'not fit for use'.

alfablue

TuckerUK wrote:

Someone should do an expose on this, what's a standard if it isn't standard?

well, as above, the standard includes a variance of 1mm, if the product is machined to fine tolerances and assumes the smaller end of the range then there is a problem.

schweiz

I had a garmin gps about 16-17 years ago that ran off AA cells. You had to peel the plastic covering off some brands of cells to fit them in and they were all alkaline.

I have some 2700mAh NiMH cells at home and they are fatter than 'normal' energizer alkaline batteries. Like Alfablue said, the ISO standard for AA cells allows for variation in cell dimension.

Tucker the ISO standard is a standard, it's not the cell manufacturers fault if the cell's dimensions are to within what is required for the standard, it's the equipment manufacturers fault for not ensuring all cells that fit within the extremes of dimensions of the standard fit in their equipment.

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

Headhuunter

schweiz wrote:

I had a garmin gps about 16-17 years ago that ran off AA cells. You had to peel the plastic covering off some brands of cells to fit them in and they were all alkaline.

I have some 2700mAh NiMH cells at home and they are fatter than 'normal' energizer alkaline batteries. Like Alfablue said, the ISO standard for AA cells allows for variation in cell dimension.

Tucker the ISO standard is a standard, it's not the cell manufacturers fault if the cell's dimensions are to within what is required for the standard, it's the equipment manufacturers fault for not ensuring all cells that fit within the extremes of dimensions of the standard fit in their equipment.

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

I don't think it's strictly true that rechargeables have 1.2V, these days they are higher, I think technology has moved on. My rechargeables pretty much always come up at 1.4-1.45V after a full charge (intelligent charger shows you MaH and voltage value for each cell)

alfablue

schweiz wrote:

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

Actually, NiMH cells will run LED lights much more efficiently than Alkalines. Alkalines start at 1.5v but will be below 1.2 by half way through their discharge, whereas the NiMH will hold their output (at around 1.4v - though nominally rated at 1.2) for 95% of their discharge. So use NiMH not Alkaline for better performance and lower cost.

alfablue

You beat me to it Headhunter

schweiz

Headhuunter wrote:

schweiz wrote:

I had a garmin gps about 16-17 years ago that ran off AA cells. You had to peel the plastic covering off some brands of cells to fit them in and they were all alkaline.

I have some 2700mAh NiMH cells at home and they are fatter than 'normal' energizer alkaline batteries. Like Alfablue said, the ISO standard for AA cells allows for variation in cell dimension.

Tucker the ISO standard is a standard, it's not the cell manufacturers fault if the cell's dimensions are to within what is required for the standard, it's the equipment manufacturers fault for not ensuring all cells that fit within the extremes of dimensions of the standard fit in their equipment.

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

I don't think it's strictly true that rechargeables have 1.2V, these days they are higher, I think technology has moved on. My rechargeables pretty much always come up at 1.4-1.45V after a full charge (intelligent charger shows you MaH and voltage value for each cell)

I've never checked the on-load voltage of my NiMH cells, They are marked as 1.2V which I accept is nominal, but I did do a test of two 'identical' lights one with new alkaline and the other with fully charged newish NiMH and the alkaline looked brighter. I then swapped the batteries round to make sure it wasn't the LED, but I still reckon the alkaline was brighter. The meter for the test was my highly calibrated Mk 1 eyeball. Maybe I was seeing what my brain expected me to see?

schweiz

alfablue wrote:

schweiz wrote:

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

Actually, NiMH cells will run LED lights much more efficiently than Alkalines. Alkalines start at 1.5v but will be below 1.2 by half way through their discharge, whereas the NiMH will hold their output (at around 1.4v - though nominally rated at 1.2) for 95% of their discharge. So use NiMH not Alkaline for better performance and lower cost.

OK. That'll teach me to draw conclusions from a 2 minute test!!

Headhuunter

schweiz wrote:

Headhuunter wrote:

schweiz wrote:

I had a garmin gps about 16-17 years ago that ran off AA cells. You had to peel the plastic covering off some brands of cells to fit them in and they were all alkaline.

I have some 2700mAh NiMH cells at home and they are fatter than 'normal' energizer alkaline batteries. Like Alfablue said, the ISO standard for AA cells allows for variation in cell dimension.

Tucker the ISO standard is a standard, it's not the cell manufacturers fault if the cell's dimensions are to within what is required for the standard, it's the equipment manufacturers fault for not ensuring all cells that fit within the extremes of dimensions of the standard fit in their equipment.

Also remember that a rechargable AA cell is only 1.2V not 1.5V so when you have a light that needs 4 cells you have a loss of 1.2V which has a big effect on light output.

I don't think it's strictly true that rechargeables have 1.2V, these days they are higher, I think technology has moved on. My rechargeables pretty much always come up at 1.4-1.45V after a full charge (intelligent charger shows you MaH and voltage value for each cell)

I've never checked the on-load voltage of my NiMH cells, They are marked as 1.2V which I accept is nominal, but I did do a test of two 'identical' lights one with new alkaline and the other with fully charged newish NiMH and the alkaline looked brighter. I then swapped the batteries round to make sure it wasn't the LED, but I still reckon the alkaline was brighter. The meter for the test was my highly calibrated Mk 1 eyeball. Maybe I was seeing what my brain expected me to see?

I must admit, when I've used disposable batts in my Fenix torch, initially it appears brighter than with rechargeables, however it seems true that the disposables drop off steadily quite soon and the light dims slowly, whereas with the rechargeables they tend to drop off suddenly at the end of the charge so you get a bright light for longer

alfablue

I think your test was correct - as far as it went. A brand new alkaline may be the brightest but not for long (2 or 3 minutes maybe), also many rechargeables will perform poorly if charged using cheap (or ultra fast) chargers rather than smart chargers - they cook them pretty quick.

Butterd2

Had similar prob with same light, but the rechargeables were too thick to fit properly. Peeled the outer label off them and they are fine now.

Harveytile

Butterd2

Had similar prob with same light, but the rechargeables were too thick to fit properly. Peeled the outer label off them and they are fine now.

Peeled batteries and all is well. Cheers for that Buttered2

OldSkoolKona

alfablue wrote:

I think your test was correct - as far as it went. A brand new alkaline may be the brightest but not for long (2 or 3 minutes maybe), also many rechargeables will perform poorly if charged using cheap (or ultra fast) chargers rather than smart chargers - they cook them pretty quick.

interesting stuff, was just thinking about rechargeables on the ride in this morning.

What would you recommend as a good recharger (for not tooo much, don't mind spending a bit extra)

Also any recommendations on good NiMH battery brands? Does it matter?

alfablue

For £14.95 delivered, I would recommend Vapextech's LCD World charger - it is a smart charger with individually monitored cells, and their AA batteries are great quality and value.

Next up, BC-700 £27.99 delivered. Adds lots of functions such as charge-discharge cycles tp refresh anbd condition batteries, variable charge rates, and a discharge function to measure capacity.

Next up BC900 more flexibility on charge rates, faster, £43.99.

Next up - the daddy: Maha Wizard One £49.99.

The BC-700 probably is the best value if you want the extra features and aren't too bothered about fast charging. All of them will maximise the life of your cells, but if you can test the cell capacity (the 3 pricier ones can) you can avoid putting a low capacity cell with a high one (once the low one is discharged it can start discharging the high capacity one), and work out when to replace them. I retire my cells when they show less than 2000mah capacity (I have the Maha).

OldSkoolKona

Cheers alphablue - who said time on here was time wasted :-)

alfablue

8) whoops, back to work

schweiz

alfablue wrote:

I retire my cells when they show less than 2000mah capacity (I have the Maha).

What do they start off at? 2900, 2700, 2300?

Is there any science as to the %age drop in capacity or just through experience?

alfablue

As for does the battery brand matter, well first off, batteries don't really provide the claimed capacity, but some are a lot better than others. My personal favourites, Vapextech 2900mah will generally offer 2450-2500mah, whereas Powerex (pretty much the best) 2700mah will offer about the same, so Vapextech are proportionately worse, but then in reality they offer the same output and for £1.25 each instead of £3 each, and having used both brands extensively, there is no difference in logevity.

Other good brands are Sanyo (aka "Fameart"), Ansmann, Accupower, GP, but I don't believe there is any NiMH AA that will deliver more than about 2600mah.

Beware some on eBay that claim 3000mah + they just won't deliver (and probably nowhere near).

There are also "Hybrid" batteries, like Sanyo Eneloop, Uniross Hybrio, Vapextech Instant etc. These come charged, and they have a very low self-discharge rate (ie they will hold 90% of their charge for maybe a year, whereas NiMH will self discharge much faster).

Whilst these have a lower capacity, typically 2000mah, they are good for items you use infrequently (like bike lights through the summer), and I use AAA Instants in my rear lights as the 40 hour run time might take several weeks or months to consume.

alfablue

schweiz wrote:

alfablue wrote:

I retire my cells when they show less than 2000mah capacity (I have the Maha).

What do they start off at? 2900, 2700, 2300?

Is there any science as to the %age drop in capacity or just through experience?

See my other post, generally the best you can get is around 2500-2600mah when new even if the wrapper states more.

I think they deteriorate over time after frequent use, things that will shorten life are very fast charge rates / high temperature, over-charging, and probably variability in manufacture. Decent smart chargers will prevent these problems (apart from manufacturing variability of course).

I was bought as a gift an Energiser "really amazingly super duper fast 15 minute" charger once - it even had a fan in it to keep things cool - after about 6 months all my cells were rubbish, running down in very short time, and until found out this stuff I was convinced that NiMH cells were hopeless!

I have about 24 AA cells on the go (mostly to power 3 bike lights, portable digital radio, garmin gps) and I reckon I buy about 12 new cells per year to keep a decent stock - so just about £15 a year.