Expected battery life with battery grip

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I've noticed that I'm using two 700mAH Li-on batteries in my 400D atm which gives over 1000+ photos without a recharge.

The battery grip also came with the capacity to deliver 6 X AA batteries which i've seen upto 2600mAH per battery.

So I could have something like 15000mAH of power for what 10k shots?? Does it scale that well or am I missing something.

sid
 
Normally, it's the voltage that adds, not the current.

Basically, iirc the AAs should last about 4x to the NB-2LH batteries you have already.

But in reality, that won't happen. You'll notice an increased life to about 2000 shots as a guess.

I don't use the AA batteries, as it's quicker to load in another proper battery into the grip instead of carrying 6 AAs with me.
 
EDITED IN THE MORNING DUE TO CLEARLY SILLY BRAIN BYPASS TYPING AT 1AM!!!!


When you use one battery it will be at a certain voltage. The device will use this voltage, the maximum power available from the battery will depend on that battery/what it is made from etc. A battery grip will offer the power of the two batteries to the camera in PARALLEL which means that the camera will get the SAME voltage. It is also possible for simple electronics in a grip to switch between batteries. If your 6 AA batteries are placed into the grip the maximum voltage would be (alkaline batteries) 1.7v x 6 = 10.2v or (NiMH batteries) 1.4v x 6 = 8.4v the camera's circuitry will be designed to work with a range of voltages converting them to the voltage required internally.

Within a range a device will draw what power it requires so if you have 1 x aa battery and connect it in a simple circuit to a bulb it will light up and glow away merrily for 10 hours (for example). If you connect 2 of these batteries together in parallel (IE pos to pos and neg to neg) then you still get 1.4-1.7v and the battery will still power the bulb at the same brightness but it will last 20 hours.

If you connect the two batteries in series (IE neg of one battery to pos of the other then the two ends not touching each other into the circuit) you ADD the voltages so you get 2.8v to 3.4v this will most likely blow the bulb up unless the bulb can handle it in which case it will glow much brighter but only last for the same 10 hours.

(note this is all rather simplified but it does sort of explain it)
 
Listen to him. He's an experienced computer user. :eek:
 
:razz:

On-topic, I've just ordered 6 rechargeable AA batteries as I prefer how much the camera weighs (it's a lot heavier). ;)
 
Kryptix said:
:razz:

On-topic, I've just ordered 6 rechargeable AA batteries as I prefer how much the camera weighs (it's a lot heavier). ;)
Click to expand...

That's all that really matters either option gives plenty of power and if the extra weight makes it feel better for you then go for it. That is the reason I got the grip for my d200 simply to increase it's size so it felt better. Each battery lasts about 400 shots!
 
cowasaki said:
When you use one battery it will be at a certain voltage. The device will use this voltage, the maximum power available from the battery will depend on that battery/what it is made from etc. A battery grip will offer the power of the two batteries to the camera in SERIES which means that the camera will get the SAME voltage. It is also possible for simple electronics in a grip to switch between batteries. If your 6 AA batteries are placed into the grip the maximum voltage would be (alkaline batteries) 1.7v x 6 = 10.2v or (NiMH batteries) 1.4v x 6 = 8.4v the camera's circuitry will be designed to work with a range of voltages converting them to the voltage required internally.

Within a range a device will draw what power it requires so if you have 1 x aa battery and connect it in a simple circuit to a bulb it will light up and glow away merrily for 10 hours (for example). If you connect 2 of these batteries together in series (IE pos to pos and neg to neg) then you still get 1.4-1.7v and the battery will still power the bulb at the same brightness but it will last 20 hours.

If you connect the two batteries in parallel (IE neg of one battery to pos of the other then the two ends not touching each other into the circuit) you ADD the voltages so you get 2.8v to 3.4v this will most likely blow the bulb up unless the bulb can handle it in which case it will glow much brighter but only last for the same 10 hours.

(note this is all rather simplified but it does sort of explain it)
Click to expand...

You've got your 'series' and 'parallel' mixed up here:D Batteries connected with the positives connected together and the negatives connected together are said to be connected in 'parallel'. Batteries connected with the positive of one battery connected to the negative of the next (and so one) are said to be in connected in 'series'.

(incidentally, the nominal voltage of an alkaline battery is 1.5 volts and a Mi NH 1.2 volts)
 
cowasaki said:
When you use one battery it will be at a certain voltage. The device will use this voltage, the maximum power available from the battery will depend on that battery/what it is made from etc. A battery grip will offer the power of the two batteries to the camera in SERIES which means that the camera will get the SAME voltage. It is also possible for simple electronics in a grip to switch between batteries. If your 6 AA batteries are placed into the grip the maximum voltage would be (alkaline batteries) 1.7v x 6 = 10.2v or (NiMH batteries) 1.4v x 6 = 8.4v the camera's circuitry will be designed to work with a range of voltages converting them to the voltage required internally.

Within a range a device will draw what power it requires so if you have 1 x aa battery and connect it in a simple circuit to a bulb it will light up and glow away merrily for 10 hours (for example). If you connect 2 of these batteries together in series (IE pos to pos and neg to neg) then you still get 1.4-1.7v and the battery will still power the bulb at the same brightness but it will last 20 hours.

If you connect the two batteries in parallel (IE neg of one battery to pos of the other then the two ends not touching each other into the circuit) you ADD the voltages so you get 2.8v to 3.4v this will most likely blow the bulb up unless the bulb can handle it in which case it will glow much brighter but only last for the same 10 hours.

(note this is all rather simplified but it does sort of explain it)
Click to expand...
AM sure you meant in parallel rather than in series. Batteries connected in series provide the combined voltage to anything on the circuit, whereas batteries in parallel provide the average voltage but with an increased capacity.
 
Yes,yes sorry bout that it was 1am and I was tired :bonk::bonk: but the descriptions of how the batteries were connected was right :) I had somehow swapped the words parallel and series round.

The nominal value for a single cell is often referred to as 1.5v but in reality an alkali battery will actually give 1.7v, a metal hydride will give 1.4v and an old rechargeable will give 1.2v

My old electronics lecturer would be laughing his head off at this...........
 
Another way to look at it is to use 'Charge Density'. Multiply the voltage x the current of each battery & add them together.

In my 50D battery grip :-

2 x Li Ion batteries , 7.4v x 1500 = 11100 x 2 (two batteries) = 22200.

or

6 x AA NiMH rechargeable, 1.2V x 2600 = 3120 x 6 (6 batteries) = 18720.

So if I use the Li Ion batteries in my grip it should/will last longer.

That's all based on nominal voltages & claimed capacity but generally speaking Li Ion batteries have a much higher capacity than NIMH batteries and don't suffer from the infamous memory effect.


Brian
 
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