rechargeable batteries for digi camera!

[ih]

apologize if incorrect forum!.Original rechargable batteries in sony digi camera are 2100Mah. i Need to get replacement. My question are below.
1. Can i use higher Mah batteries. (i have 2300Mah)
2. there is also a sony charger for the same is it ok to recharge 2300 Mah if the answer to question 1 is yes.
thanking all in advance.
ih

 

[plugwash]

What type of battery is this?

Generally with batteries as long as the size and connections are the same the capacity being a bit different shouldn't be an issue.

 

[ih]

sorry forgot to mention. The batteries are AA- HR6- nimh- 1.2v rechargeable.
thanks

 

[timtheenchanter]

Itll be fine, it means one of two things, depending on how "intelligent" the charger is,
1. the 2300s will never get fully charged, not a problem for NiMh or
2. they will last longer (ie you will get more photos per charge.)

 

[ericmark]

No problem as long as both NiMh but old NiCad chargers had a host of ways to sense charge. Simple types that take 16 hours to charge are no problem but some of the fast chargers may have problems.

I think you would be advised to monitor first charge and just see how warm both the charger and batteries get.

Seems simple but most people miss the fact that if a constant current goes into a battery while it is being changed into chemical energy the battery will be cool but as soon as charged the charge is turned to heat. So as soon as batteries start to warm then they are charged.

Of course there always will be slight heat produced as no process is perfect.

 

[JamesA]

Probably too late, but I'd recommend getting a job lot of rechargeable batteries from Hong Kong on ebay. They tend to be 2500.
This has saved us a fortune on powering the kids' toys and helped the environment as we no longer buy disposable batteries.

You should avoid keeping your charged batteries anywhere hot, so keep them out of the sun.

The rapid chargers always had a bad name for damaging the batteries, so I went for a traditional overnight one.

One site pointed out that the easiest way of damaging a battery is overcharging it. Therefore you may be better off with a charger that switches off or set a reminder in your phone when they need turning off.

 

[ericmark]

It seems there are many ways that a charger can sense when a battery is charged. I had a really expensive charger that monitored the voltage and as the battery charges with a constant current charger the voltage raises then as it becomes fully charged drops a little. The charger sensed this drop then reduced charge rate and continued for fixed time. It also checked voltage when battery was inserted and if not discharged it discharged battery first. We found that a pain as if anyone unplugged the charger and plugged it back in it would discharge all the batteries. It charged 6 radio batteries and cost around £300 so unlikely to be used for domestic. It would charge different voltage batteries all mixed up on same charger.

As we reduce in price simpler methods are used and the charger with lid over the battery so it can monitor temperature has become popular. The problem is unless a fairly high charge rate is used the battery temperature will not rise so they all tend to be rapid chargers.

Another common method is time and either inserting the battery pushes a switch or there is a start button on the charger even in some cases the battery voltage triggers the charger. It relies on only flat batteries being put into the charger or it has a auto discharge and then charges for a set time. With auto discharge half charged batteries take longer to charge than fully discharged.

However what ever method is used batteries charged using a charger which stops once charged tend in general to last longer than those where a trickle charge is used. We only have to look at our mobile phones where the battery is given a hard life really but they still last for years.

Storing batteries is a problem. In theory acid batteries are stored charged and alkaline batteries are stored discharged. The NiCad falls into the latter and new batteries are normally supplied discharged. However they can grow crystals inside the battery which short them out. If the battery is charged as the crystal grows it will be burnt off as soon as it shorts out but if the battery is flat it will not and then the charger does not produce enough current to burn off the crystal so battery is useless. I have seen capacitors discharged across a battery to revive it but it is a dangerous process and only works where you have access to single cells. So although in theory they should be stored discharged once in service it is better to leave with at least some charge so if a crystal grows it will be zapped.