If i run 2 18650 batteries that have lets say 2000mAh and a continuous discharge rate of 10 amps and run 2 in parallel i know that it would change to 4000mAh and stay at same 4.2 volts on a fresh charge but would the continuous discharge rate stay at 10 amps or would it also double to 20?
18650 in Parallel
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Yes, with two identical batteries in parallel, each battery provides half the total current.
Only the mAh's double when batteries are used in parallel . Amps and voltage stay the same as using a single battery.
If stacked, the voltage doubles, but the mAh and amps stay the same as using a single battery (not adviseable).
If stacked, the voltage doubles, but the mAh and amps stay the same as using a single battery (not adviseable).
One of the best questions I have seen posed by a first post. Baditude is correct. Let me just say welcome to the forum and happy vaping!
It's not advisable to stack batteries for your own safty. But again if they are in parallel amps and mah will stay the same to answer your questions. However still not advisable. The inherent risk is one will discharge faster than the other.
Amps will not double. Only mah if ran in parallel, but like what realsis said, there is a high chance one battery will be depleted faster than the other.
Your basic reasoning is not wrong and running batteries in parallel spreads the load over both batteries, as opposed to running in series.
However not every li-ion can be run in parallel (see manufacturer data sheet for individual cell specs, if and to how many a cell can be paired ,etc) and pairing those that can requires fresh , identical batteries. Once paired the need to remain so during charge/discharge.
If you still have to ask these questions please don't attempt it yet.
There is plenty information online ... As a starter What do I need to know about paralleling Li-ion / Li-poly batteries - Page 1
Again, its better to educate yourself before attempting something unknown however there is no reason not to educate yourself and then attempt something
If everybody would listen to the scared ones , we all still be living in dark caves.
Be smart, be safe , vape on...
However not every li-ion can be run in parallel (see manufacturer data sheet for individual cell specs, if and to how many a cell can be paired ,etc) and pairing those that can requires fresh , identical batteries. Once paired the need to remain so during charge/discharge.
If you still have to ask these questions please don't attempt it yet.
There is plenty information online ... As a starter What do I need to know about paralleling Li-ion / Li-poly batteries - Page 1
Again, its better to educate yourself before attempting something unknown however there is no reason not to educate yourself and then attempt something
If everybody would listen to the scared ones , we all still be living in dark caves.
Be smart, be safe , vape on...
I don't mean to disagree with you, and I realize you're a wealth of knowledge on this forum when it comes to batteries. But I have to disagree with this statement. When any constant voltage source (i.e. battery) is connected in parallel with another, the current drain will be halved between the two. In other words. if we had a circuit that had a 20 amp drain, then using 2 batteries in parallel will result in ~10 amp drain on either battery. Now I said about for a reason... This is why batteries in parallel must be closely matched... Typically the cells are chosen that have VERY close statistics (internal resistance, depth of discharge, etc) and then cycled together to get them matched as close as possible. They are then kept in parallel and always cycled together. The reason for this is the same reason as my about... If the discharge curve of one battery isn't matched to the other, then the voltage of one cell can be higher or lower than the other. In this case, the voltage differential will also result in a current differential... In other words, in a 20 amp drain, instead of having 10 amps on each battery you could end up with 13 amps on one and 7 on the other... Depending on load... Which, especially when dealing with high loads pushing batteries to the limits could result in pushing one of the batteries beyond it's capabilities...
Exactly, batteries in parallel is how they achieve higher amp ratings on multi cell packs.
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