I’m not sure if this is a valid question, but will how the batteries are arranged in either of these two components affect power (current) delivery? I read something about parallel series?
Option 1:
Option 2:
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The two units are both series-connected, and will both supply 7.2v. As far as voltage or current supply is concerned, they are identical.
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What if I need to supply more than 7.2V? My plan is to use 6 X 1.5V AAs - will that cause problem? It’s being plugged into an Ardunio to power a small vehicle prototype that shoots water (for university).
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As in, the water pump used needs 9V to work. Would a regulator increase the power if I were to use 1.2 AAs X 6?
Hi Rochelle
These battery holders would be series connected (6 X 1.2 = 7.2). The difference would be in layout. One has the 6 cells side by side the other in 2 groups of 3 side by side stacked one above the other.
Cheers Bob
EDIT: Disregard this I didn’t scroll down to view the other replies.
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You can boost the vaoltage from a battery supply using a product such as this:
You need to confirm that the booster can supply the current required by the pump. Also, it would be preferble to find a battery arrangement that provided the 9v directy, as it will be more efficient.
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The battery holder description states: This battery holder can hold 6 AA battery which can make 7.2 V rechargeable battery pack from NiMH / NiCd cells or 9V battery pack from alkaline cells.
Can I use 1.5V Lithium - would that be safe? - Energizer Ultimate Lithium AA Batteries 4 Pack | Officeworks
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As they are available in places like Woolworths I don’t see why they would not be safe. Other more experienced users of Lithium might know more about his.
Cheers Bob
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Yes, those lithium cells are alkaline replacements, and yes you could get 9v out of them. They are non-rechargeable, and use a different battery chemistry to 3.7v rechargeable lithium-ion cells.
This is a pretty good summary article:
And for reference, an Arduino Uno or Nano has a recommended input voltage range of 7v-15v, but you can usually get away with anything from 6v-20v for shorter periods.
One thing that’s important to keep in mind when you start stacking batteries in series to up the voltage, is that they almost never output their nominal voltage rating, just close to it.
NiMH will output ~1.4v/cell fully charged, down to ~1.0v when dead flat.
Alkalines will output ~1.65v fully charged, down to ~1.3v when dead flat.
1.5v Lithium AAs will output ~1.7v fully charged down to ~1.2v when dead flat.
3.7v Lithium-Ions will output ~4.2v fully charged down to ~3.0v when dead flat.
For one or two cells, the difference from nominal is small, but when you start stacking them up to boost the voltage it really starts to make a difference in absolute terms. Eg. with 8x Nimh’s in series, that pack would output 11.2v-8.0v, while 8x Alkalines will output 13.2v-10.4v. If your device can only handle an absolute max of 12v before burning up, or needs at least 11v to work, you can see how this difference becomes important.
If you want some more tech detail on those Lithium AA’s, check out this datasheet from Energizer:
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Thank you so much, Oliver! I’ve actually been doing some calculations already with that PDF, but thank you so much for that detailed response, really helpful.
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Also as well, could you recommend a really good YouTube video etc to clarify how to regulate voltage? We’re building a small RC car-type vehicle that pumps out water. There are going to be different current needs for the systems. I’m not sure how to regulate, for example, a water pump that needs 9V while a motor may need something else? It’s the placement of the regulators I am guessing…a circuit schematic would help, just not sure how to draw it, as I don’t know what would go into it…Sorry if that’s vague.
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This article covers it pretty well:
And this bloke’s pretty good:
And this video covers the theory of operation pretty well:
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