/ Rechargable AA's for a headtorch - any battery geeks?
My knowledge pretty much finishes with "the more mAh the better", which is probably far from the whole story. For example I'm guessing that some ebay 2900mAh batteries from china are going to be rubbish compared to a higher quality set of 2600mAh.
I was wondering if I should just pick up a set of AA 2500mAh NiMH from the supermarket or if I'd notice much difference with a higher capacity set. There's a charger and set of 4 Ansmann 2850mAh for £17 here (http://tinyurl.com/cqtdun4) which seems like good value.
Any other insights into rechargeable batteries would be welcome: Are there any disadvantages to getting a set with higher mAh? Are there any other things to look for? Can you pretty much charge any rechargeable battery with any charger or are there chargers to avoid/features to look out for? Is Ni-MH the only option with rechargable AA's or are there better alternatives?
A lot of rechargable AA batteries put out 1.2v instead of the 1.5v put out by 'normal' cells. I don't know if your head torch will like that.
As for voltage. When the battery is under load, Alkaline batteries drop in voltage while NiMH don't. NiMH has a more consistent output in voltage and have a higher possible discharge rate.
English: Using NiMH the battery a directly driven powered light will not dim as much during use and is able to power more powerful lights.
As for NiMH:
More Mah = more stored power, but it loses it's power during storage more rapidly. 2500 - 2700 Mah is only useful when you expect to drain the batteries in 2 weeks.
If you plan to use the batteries for a longer period of time, go for 'Low self-discharge' NiMH, like Sanyo Eneloops or GP Recycko's. They are only 2000 - 2100 Mah, but the batteries barely drain power when not in use.
Which tip AA rechargeables uniross 2400 premium hybrio, energizer accu, go recyko, maplin create hi capacity, ansmann digital.
Use uniross hybio in my rxp.
I guess the ideal option would be to have the choice of using both, the higher capacity ones for short term discharge and the longer life ones for going away. Would both types of battery charge in the same charger?
What tjin and mountain Lion say
Get hybrios or eneloops they keep their charge in storage much better so are ready when you need them, also they are now available in 2300/2400 mAh versions. I just got some uniross 2400 series hybrio and they are good.
A NiMH charger should be able to charge any NiMH that dit in to the slot. I do recommend a charger with independed bays. This allows each battery to be fully charged.
Charging in pairs mean one is always under charged and the other over charged.
+1 for Sanyo Eneloop
With independent bays, i mean each slot is tested, chargers and meassured seperatly. This allows each battery to be charger fully. For example chargers such as Maha powerex MH-C9000.
Good batteries can still end up being crappy when using a cheap/bad charger.
Given they're the same price and both from decent manufacturers, if the only difference is in self-discharge rate then presumably in a fast discharge application the higher capacity batteries would be more suitable.
Re. the Maha powerex MH-C9000, £50 is quite a price for a charger. Is there really much noticeable difference between that and you're run of the mill £20 chargers?
The MH-C9000 is one of the best. But most Maha chargers are good.
Other alternatives are: BC-700 charger (sold under various brand names)
The higher capacity Ansmann are not of the LSD low self discharge type (the limit on these is about 2300/2400mAh with current technology) so they will lose power in storage much faster - ie when lying in your torch unused for a few weeks, the new LSD types will still have most of the charge power after several months - very useful when you go to get a torch out when the s,,, hits the fan and your not sure the last time you topped up the charge.
> The higher capacity Ansmann are not of the LSD low self discharge type (the limit on these is about 2300/2400mAh with current technology) so they will lose power in storage much faster - ie when lying in your torch unused for a few weeks...
Thanks for your reply, I might end up going with some lower capacity pre-charged in the end although I still like the idea of making the most of the battery life by getting the extra capacity ones. I don't think the self discharge will be a massive problem during the winter (it would be unusual for me to go 3 days without using a head torch let alone a few weeks) but I guess it would come in handy during the summer, not having to top them up as often. I'm not really sure how much an extra 450mAh would give you anyway.
Don't bother with crap batteries off ebay, it's full of cheap rubbish from China nowadays. Get some proper Eneloops from a decent supplier - there's a few online UK companies, I used 7dayshop.com
As for alternatives, NiMh is the only really practical option at the minute. I did look into lithium technology - non-rechargeable lithium cells are a good backup solution (lightweight too and good in the cold), but there's no AA-sized rechargeable lithium cells around yet.
Elsewhere on the site
Pete Whittaker has flashed the 32 pitch route Freerider 5.12d on El Capitan in Yosemite Valley over three days,... Read more
Manchester Climbing Centre is showing Reel Rock’s Valley Uprising on Tuesday the 11th of November at... Read more
Last year, Finn McCann wrote an article about climbing El Capitan with his terminally ill father Seamus, who had been... Read more
A fantastically versatile little pack; whether out running in the hills, hitting the trails on the bike or just running for the... Read more