Rechargeable Batteries

schnipps

schnipps

schnipps

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I have 2 outdoor solar lamps and seemingly they came with uttery rubbish rechargeable batteries that after 4 weeks dont charge up atall so i get no light at dusk no matter how sunny it is through the day.

I want to replace the batteries with some better ones as they are no brand chinese things. They are AA 600mAH 1.2V, now does anyone know what the 600mAh means as you can get ones with higher ratings, im unsure if i can just put anything in there or if im best to stick to those numbers or it just wont charge from the solar panel.

Any ideas?
 
Chuck in the biggest rating you can find (our cordless phones are running cheapo ebay 1300mah AAA batteries and have been in for about 2 years.).

The higher the numbers the longer it can sustain the output.
 
As per SB,
The higher the mAH numbers the longer it can sustain the output.

stick to the 1.2v though :D
 
Sanyo Eneloop ones are hybrid NiMhs that hold up to like 80% of their charge unlike regular rechargeable thats lose them when they sit there.

They are not exactly expensive and the AA ones I use are 2000mAh they last forever! :D
 
I'd normally say hybrids, but in this case it doesn't really make even the slightest difference.

However, a 600mAh rating is very much NiCad territory, and if that's the case, they might not actually charge Ni-MH at all (or at least not very well).
 
Hey probably too late since you bought them already but I work in the lighting department at a john lewis store and now a little about solar lights.

the mah reffers to milliamp hour and quite rightly the larger the number the longer the battery lasts but you do have to remember a few things.

1: The batteries will only charge to a limit as the solar panel will allow. 600mah should be enough to last the night and still fully charge the next day. These batteries are better to be full and empty than charging when part full.

2: Standard batteries that are charged from the mains use a constant recharge rate, meaning whatever it's like outside, when they're plugged in the wall they're always at the same rate.

Solar rechargable batteries however use the trickle charge process and take whatever power it can and stores it.


Solar Batteries are normally 600mah and the recommended charge times are as follows;

Quick Charge: 1.5 hours at 600mA
Standard Charge: 15 hours at 60mA

Another thing is most solar batteries just need sunlight, not direct light, so if it's in the shade it should still charge.

Hope this helps


edit: sorry forgot to mention something, what Berserker says is right, these batteries are nickel cadmium based
 
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Almost all solar lights contain el-cheapo Ni-Cd batteries.

Usually they won't charge Ni-MH, though the odd expensive (£50+) sets do.
 
According to a guy I was in a meeting with about electric cars a few months ago, batteries are better part discharged and recharged than they are fully discharged and recharged as it puts less stress on the electrolyte. This is assuming that they dont suffer from memory effect (which I think Ni-Cad's do :o )

Wiki....
Depth of discharge (DOD) is normally stated as a percentage of the nominal ampere-hour capacity; 0% DOD means no discharge. Since the usable capacity of a battery system depends on the rate of discharge and the allowable voltage at the end of discharge, the depth of discharge must be qualified to show the way it is to be measured. Due to variations during manufacture and aging, the DOD for complete discharge can change over time / discharge cycles. Generally a rechargeable battery system will tolerate more charge/discharge cycles if the DOD is lower on each cycle. [3]

duracell.com claims that rechargeable batteries do not have a 'memory effect'.
Click to expand...
 
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nokinidea said:
According to a guy I was in a meeting with about electric cars a few months ago, batteries are better part discharged and recharged than they are fully discharged and recharged as it puts less stress on the electrolyte.
Click to expand...

This only applies to lithium batteries. Nickel batteries should always be fully discharged before recharging.

It is for this reason that I would question putting a higher capacity battery in the lights, as this means they will not fully discharge during the night.

I may well be wrong :)
 
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