Standard 2aH LiPO in parallel?

Hello Particle community,

I have a quick pretty much yes/no question. (sorry if this is a stupid question)
Is it possible to put the standard 2000mAh LiPO’s that comes with the Electron kit in parallel with another just as it is? Is it theoretically possible to have unlimited 2Ah LiPOs in parallel?

I want a higher capacity LiPO that can handle a long time in the field (years) with my 6w Voltaic solarpanel. It’s very cloudy pretty much year around and a lot of trees could potentially shade, so the solar panel can only do so much. I was thinking of putting 5 in parallel to get a 10aH battery pack.

Thanks!

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Hi Mic, I was about to tell you I would never do such a thing, but I googled a bit and apparently it can be done and it is done:
https://www.quora.com/What-would-happen-if-two-batteries-connected-in-parallel
I’ve never done it, though.
Gustavo.

If you can get by with 6600 mAh, the Adafruit 3.7V LiPo batteries are all compatible, and even have the same JST-PH battery connector with the correct polarity, so you can just plug them in and they’ll work.

@rickkas7 the thing is… i can’t get these kind of batteries shipped from non-european places via USPS (Which is the only available shipping method i can choose on Adafruit.com). It has to be a european site and even then it’s still not certain that it can be shipped. That’s why i thought combining the 2 mAh LiPO batteries from Particle could be an alternative.

Digikey.com stocks many Adafruit items including that battery. Since they ship from the United States so you might run into trouble as well, but it’s worth checking.

Yes you can parallel them together to increase capacity.

You can also just get larger sized batteries to avoid using many smaller cells.

You can buy a 10Ah cell vs having 5 x 2Ah cells.

Just make sure you have a Protection PCB attached the battery to protect against short circuit, under and overvoltage conditions.

Here is a place with tons of different battery options: http://www.batteryspace.com/li-ionsinglecell.aspx

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Its also a good idea to make sure each battery is at the same charge level before you connect them - otherwise you may have a full one trying to charge an empty one in an uncontrolled manner. Newly purchased cells should be in more or less the same state-of-charge (usually about 50% as this extends the shelf life of the cells).

I have a product with two Li-ion cells in parallel to achieve 6500mAh of capacity, and I’ve had no issues.

Good tip.

Best way to make sure they are close to the same State of Charge is to charge each battery to full individually and then connect them after both are at the same charge level.

Just be aware paralleling LiPo is not something to take lightly.
For farting around to prove a concept it’s not a real big problem. But if your plan is to make a product to sell, I would discourage you if using non protected cells. A 10AH pack has allot of energy and if shorted will most likely catch on fire.
If the batteries you are using do not have protection circuitry, this is NOT something you should do. For instance, there are 2 versions of the 18650 battery, with and without the protection circuit built into the battery.

The issue is should one cell take a crap, the rest will try to yam all their charge into it. If no protection per cell is included you could very well end up with a fire, or at the very least a puffy pack.

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Even with battery protection circuits attached to the battery pack the cells are still dangerous and need to be handled carefully :fire: :fireworks:

Yeah it would be optimal to not have my application burst into flames like that :sweat_smile:

I can’t order lithium batteries from any US website shop I’ve seen (including Adafruit, Sparkfun, Batteryspace and Digikey), but I found a more battery focused company website that might do the trick: https://voltaplex.com. I think it’s still a US company but I’m hoping they might have storage in Eu or at least outside of US.

I won’t make my own parallel LiPo pack from the standard 2Ah batteries, I’ll leave that to more qualified people for now as I don’t want to accidentally burn places down and/or hurt somebody.

Nonetheless, thank you for your answers, much appreciated!

You should be able to get it from here. Though you would need to solder your own wires on the tabs.

It actually ships to my country :open_mouth:
Thanks for the link!

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I would not do this. Although you might get away with it if both batteries have the same health and state of charge, but they also might not. LIPOs are not very tolerant of mismatches. Battery manufacturers go through significant pains to match and balance batteries before connecting them and then add circuitry to protect them.

Most definitely do not charge them connected.

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We have repeatedly recommended that he make sure the cells have a battery protection circuit attached to each battery cell.

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