<p>LiPo batteries are a pain to work with, you should <em><strong>NOT</strong></em> attempt any modification or grouping of cells, given your current electrical knowledge.</p>
<p>Those batteries can throw a <em><strong>MASSIVE</strong></em> hissyfit ending in a very real BOOM that could kill people nearby, in just a few seconds AFTER the shortest amount of time in a shorted circuit/bad contact.</p>
<p><strong>Professionals</strong> are making those battery packs and include a lot of securities to prevent such events between cells of the same pack, you should NOT take it lightly.
The energy density of those is nowhere near the old NiCd batteries (think at least 3 times higher).</p>
<p>Never short the pack itself, never try to make your own &quot;pack&quot; until you have sufficient knowledge.</p>
<p>Just to emphasize, we're talking <em><strong>CRATER IN THE GARDEN</strong></em> type of RUD (Rapid Unscheduled Disassembly)
It's because of the way those battery terminals work, and even an &quot;instant&quot; shorting can start a chain reaction (look up for Thermal Runaway) that can propagate VERY quickly and in a matter of SECONDS make the whole battery go VERY bad.</p>
<p>Ask yourself if you prefer to have multiple packs and change them regularly, or if you prefer a single heavier pack you won't have to change.</p>
<p>if a small one goes bad, you might discard it easily and reduce/avoid damage to you, your car, or RC model (Think &quot;live grenade&quot;, but crossed with a miniature cat hissing at you. GET those emergency release handles).</p>
<p>if a big one goes bad, exit the vehicle/area and run away screaming for cover.</p>
<p>Having a battery case seems like a very good idea with LiPo.</p>
<p>Just to reiterate over the actual danger, and give you some perspective :
1kg of LiPo battery (on full charge) is having the equivalent energy to about 230g of TNT.</p>
<p>The Mark-II &quot;Pineapple&quot; grenade, that you can see in every war movie, contains 52g of TNT. So your kilo of LiPo battery is about 4 and a half grenades... probably less confined than the cast iron body of a grenade, but those grenades weren't peppering you with lithium...</p>
<p>Your small battery is about 286g, including the wiring and plastics. I think it's about safe to assume 250g of it is the LiPo part.</p>
<p>Still more energy than a grenade.</p>
<p>Your big battery is 910g, still about 4 grenades...</p>
<p>Now you know, be careful with those, Never hesitate to ask a professional about it, There is no shame in being careful for yourself and others.</p>

CC BY-SA 4.0
2024-08-23T14:35:40.367Z
They don't go up like a grenade, though--total energy isn't the same as energy release rate.  The threat is burns, not supersonic fragments.  Just look at cars:  Even Hollywood cars don't leave big craters even though the gas tank has energy comparable to larger aircraft-delivered bombs.
Loren Pechtel
CC BY-SA 4.0
2024-08-27T17:03:39.987Z
A kilogram of steak has the equivalent energy of about 600 grams of TNT. Why did they bother with TNT when they could make 12 grenades from one large steak?
Chris
CC BY-SA 4.0
2024-08-22T16:32:57.647Z
2024-08-22T16:32:57.647Z
Beware
<p>the battery capacity in parallel increases as a factor of the batteries mAh rating so 3 x 5000 (should be the same ratings) = 15,000 at 7.4volts (111 watt-hours).
However, your question seems to be more series oriented - so 7.4v cells x 3 gives you 22.2volts at 5000mAh (still 111 watt-hours).
It is important in a series combination that you should have battery management for balancing otherwise a weak cell will impact the whole group.</p>

CC BY-SA 4.0
2024-08-22T05:48:52.813Z
2024-08-27T15:39:27.200Z
2024-08-27T15:39:27.200Z
webmaker
<p>3 7.4V batteries will need to be placed into series to reach 22.2V. When batteries are placed into series, their capacities don't add and you're left with basically a 22.2V 5000 mAh battery.</p>
<p>You would have to buy 9 batteries and put 3 of them in series and then put all 3 sets of those in parallel to get to 22.2V and 15000 mAh. You shouldn’t do this, though. To properly use multiple lithium batteries at once there should be some circuitry to balance the loads on the batteries and protect them. If the parallel cells aren't exactly the same voltage they will drain each other. Best case scenario this dramatically decreases the effective capacity and lifetime. Worst case scenario it starts a fire.</p>

CC BY-SA 4.0
2024-08-23T14:29:55.640Z
It's series that require the protective circuitry.  Parallel could be an issue when you put the pack together if they aren't at equal charge, but once they have been equalized they'll always stay equalized as charge will preferably go into the weakest and power will preferably come from the strongest.
Loren Pechtel
CC BY-SA 4.0
2024-08-23T14:56:50.803Z
@LorenPechtel That's a bit of an oversimplification. Suppose one battery has slightly lower internal resistance than the others. Under load, this battery will be drained faster. But when the load is removed, it will be at a lower voltage, and so charge will flow from the other batteries to recharge the lower resistance one.
Chris
CC BY-SA 4.0
2024-08-23T16:34:05.123Z
Yeah, but that's not a big enough effect to need protective circuitry.  You need protective circuitry to ensure a weaker cell in the series chain never gets negative bias, nor makes the charger deliver power to a fully charged cell.
Loren Pechtel
CC BY-SA 4.0
2024-08-21T17:38:22.123Z
2024-08-21T17:38:22.123Z
Chris
<p>I was planning to buy batteries for a RC Airplane which requires 22.2V of LiPo battery. There was the option to buy a single 6000mAh 22.2V LiPo battery but I figured that I could also use 3 7.4V 5000mAh batteries to receive the overall mAh to be 15000. Is this logic correct?</p>
<p>If yes, then how can the overall weight of 3 such batteries be less than that of a single 6000mAh battery? <a href="https://www.motionrc.com/products/admiral-5000mah-2s-7-4v-50c-lipo-battery-with-ec5-connector-epr50002e" rel="nofollow noreferrer">This is the 7.4V battery</a> and <a href="https://www.motionrc.com/products/admiral-pro-6000mah-6s-22-2v-50c-lipo-battery-with-ec5-connector-epr60006e" rel="nofollow noreferrer">this is the 22.2V battery</a>.</p>

CC BY-SA 4.0
2024-08-22T20:12:07.393Z
This is why the fairest measure of battery capacity isn't mAh, but watt-hours (Wh). Regardless of whether you wire batteries in series or in parallel, the overall capacity in Wh will always be the sum of the Wh of each battery.
gparyani
<lipo-batteries>
Does the overall mAh of the battery add up when batteries are parallel?
Sambhav Khandelwal
# Does the overall mAh of the battery add up when batteries are parallel?

(Asked by: username_0 on 2024-08-21)

I was planning to buy batteries for a RC Airplane which requires 22.2V of LiPo battery. There was the option to buy a single 6000mAh 22.2V LiPo battery but I figured that I could also use 3 7.4V 5000mAh batteries to receive the overall mAh to be 15000. Is this logic correct?

If yes, then how can the overall weight of 3 such batteries be less than that of a single 6000mAh battery? [This is the 7.4V battery](https://www.motionrc.com/products/admiral-5000mah-2s-7-4v-50c-lipo-battery-with-ec5-connector-epr50002e) and [this is the 22.2V battery](https://www.motionrc.com/products/admiral-pro-6000mah-6s-22-2v-50c-lipo-battery-with-ec5-connector-epr60006e).

**Tags:** lipo-batteries
> **Comments:**
> **username_1**: This is why the fairest measure of battery capacity isn't mAh, but watt-hours (Wh). Regardless of whether you wire batteries in series or in parallel, the overall capacity in Wh will always be the sum of the Wh of each battery.  

---

## 3 answers

### Answer by username_4 on 2024-08-21. Score: 9 | Accepted answer

3 7.4V batteries will need to be placed into series to reach 22.2V. When batteries are placed into series, their capacities don't add and you're left with basically a 22.2V 5000 mAh battery.

You would have to buy 9 batteries and put 3 of them in series and then put all 3 sets of those in parallel to get to 22.2V and 15000 mAh. You shouldn’t do this, though. To properly use multiple lithium batteries at once there should be some circuitry to balance the loads on the batteries and protect them. If the parallel cells aren't exactly the same voltage they will drain each other. Best case scenario this dramatically decreases the effective capacity and lifetime. Worst case scenario it starts a fire.

> **Comments:**
> **username_3**: It's series that require the protective circuitry.  Parallel could be an issue when you put the pack together if they aren't at equal charge, but once they have been equalized they'll always stay equalized as charge will preferably go into the weakest and power will preferably come from the strongest.  
> **username_4**: @LorenPechtel That's a bit of an oversimplification. Suppose one battery has slightly lower internal resistance than the others. Under load, this battery will be drained faster. But when the load is removed, it will be at a lower voltage, and so charge will flow from the other batteries to recharge the lower resistance one.  
> **username_3**: Yeah, but that's not a big enough effect to need protective circuitry.  You need protective circuitry to ensure a weaker cell in the series chain never gets negative bias, nor makes the charger deliver power to a fully charged cell.  

---

### Answer by username_2 on 2024-08-22. Score: 4

LiPo batteries are a pain to work with, you should ***NOT*** attempt any modification or grouping of cells, given your current electrical knowledge.

Those batteries can throw a ***MASSIVE*** hissyfit ending in a very real BOOM that could kill people nearby, in just a few seconds AFTER the shortest amount of time in a shorted circuit/bad contact.

**Professionals** are making those battery packs and include a lot of securities to prevent such events between cells of the same pack, you should NOT take it lightly.
The energy density of those is nowhere near the old NiCd batteries (think at least 3 times higher).

Never short the pack itself, never try to make your own "pack" until you have sufficient knowledge.

Just to emphasize, we're talking ***CRATER IN THE GARDEN*** type of RUD (Rapid Unscheduled Disassembly)
It's because of the way those battery terminals work, and even an "instant" shorting can start a chain reaction (look up for Thermal Runaway) that can propagate VERY quickly and in a matter of SECONDS make the whole battery go VERY bad.

Ask yourself if you prefer to have multiple packs and change them regularly, or if you prefer a single heavier pack you won't have to change.

if a small one goes bad, you might discard it easily and reduce/avoid damage to you, your car, or RC model (Think "live grenade", but crossed with a miniature cat hissing at you. GET those emergency release handles).

if a big one goes bad, exit the vehicle/area and run away screaming for cover.

Having a battery case seems like a very good idea with LiPo.

Just to reiterate over the actual danger, and give you some perspective :
1kg of LiPo battery (on full charge) is having the equivalent energy to about 230g of TNT.

The Mark-II "Pineapple" grenade, that you can see in every war movie, contains 52g of TNT. So your kilo of LiPo battery is about 4 and a half grenades... probably less confined than the cast iron body of a grenade, but those grenades weren't peppering you with lithium...

Your small battery is about 286g, including the wiring and plastics. I think it's about safe to assume 250g of it is the LiPo part.

Still more energy than a grenade.

Your big battery is 910g, still about 4 grenades...

Now you know, be careful with those, Never hesitate to ask a professional about it, There is no shame in being careful for yourself and others.

> **Comments:**
> **username_3**: They don't go up like a grenade, though--total energy isn't the same as energy release rate.  The threat is burns, not supersonic fragments.  Just look at cars:  Even Hollywood cars don't leave big craters even though the gas tank has energy comparable to larger aircraft-delivered bombs.  
> **username_4**: A kilogram of steak has the equivalent energy of about 600 grams of TNT. Why did they bother with TNT when they could make 12 grenades from one large steak?  

---

### Answer by username_5 on 2024-08-22. Score: 2

the battery capacity in parallel increases as a factor of the batteries mAh rating so 3 x 5000 (should be the same ratings) = 15,000 at 7.4volts (111 watt-hours).
However, your question seems to be more series oriented - so 7.4v cells x 3 gives you 22.2volts at 5000mAh (still 111 watt-hours).
It is important in a series combination that you should have battery management for balancing otherwise a weak cell will impact the whole group.


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