<p><strong>Note: This answer does not consider whether this is a 'good idea', as there can be safety concerns with over-discharged lithium batteries (e.g. see <a href="https://drones.stackexchange.com/q/304/68">this question</a>.)</strong><br />
I aim here to address the 'how' of the question, but you must decide if you consider the risks acceptable (for this battery, or others in the future) and follow all the usual charging safety measures.</p>
<p>It looks like the charger in question supports unbalanced charging, so you may be able to set the battery to charge in unbalanced mode which should ignore the per-cell voltage. In this case, I would set the charge current as low as possible and charge somewhere very fireproof - in case the low cell voltage has caused damage - and plan to stop the charge once the faulty cell has exceeded about 3.1V. You should then be able to try balance charging again.</p>
<p>However, the charger may check the sum of the individual cell voltages for the unbalanced charging mode and could therefore still decide that the total voltage is too low.</p>

CC BY-SA 4.0
2020-11-15T21:02:50.297Z
2020-11-15T21:02:50.297Z
Kralc
<p>The Li-ion Pack has 4 18650 lithium-ion batteries with a soldered Balancer and XT60.
On my ISDT charger, the read out voltage for each battery cell is:</p>
<ol>
<li>3.17V</li>
<li>3.18V</li>
<li>3.29V</li>
<li>2.93V</li>
</ol>
<p>Whenever I try to charge the Li-ion Pack, I get:</p>
<ul>
<li>&quot;This operation is not supported&quot;</li>
</ul>
<p>My Question:
How can I bypass this using my ISDT charger?</p>
<p><a href="https://www.racedayquads.com/products/auline-14-8v-4s-18650-2600mah-1c-li-ion-battery-w-built-in-protective-board-for-dji-goggles-xt60?_pos=5&amp;_sid=e633cb311&amp;_ss=r" rel="nofollow noreferrer">Auline 14.8V 4S 18650 2600mAh</a></p>
<p><a href="https://www.racedayquads.com/products/isdt-q8-500w-20a-charger?_pos=1&amp;_sid=4f8e8dbb5&amp;_ss=r" rel="nofollow noreferrer">ISDT Q8</a></p>

CC BY-SA 4.0
2020-11-15T00:24:49.037Z
Could you link to the product you're talking about? I haven't ever heard of the LionPack.
ifconfig
CC BY-SA 4.0
2020-11-15T00:27:35.420Z
@ifconfig I believe it's a Lithium ion battery. I've seen both "Li-ion" and "lion" as abbreviations.
Jacob B
CC BY-SA 4.0
2020-11-15T00:32:57.117Z
Sorry about that, I just added the product links.
DroneDome
CC BY-SA 4.0
2020-11-15T00:39:10.070Z
@DroneDome it might not be charging because of a safety feature built into the charger. If there are cells with 3.17v and 2.93v in the same battery, that could mean there is a problem with one or more of the battery cells, which could be very dangerous. If the battery is new, I would recommend contacting the seller and asking if they can replace the battery.
Jacob B
CC BY-SA 4.0
2020-11-15T01:11:14.883Z
@Jacob B, I thought you can discharge a lithium-ion as low as 2.5 - 2.7v and still be able to salvage it? And yes, the battery is new
DroneDome
CC BY-SA 4.0
2020-11-15T01:28:03.980Z
@DroneDome, no that's not correct. Discharging below ~3.0 V/cell irreparably damages the cells.
ifconfig
CC BY-SA 4.0
2020-11-15T01:29:04.877Z
@DroneDome yes, you can discharge a Li-ion to a voltage of ~2.8v or 3.0v, but in any series battery (lipo and Li-ion) the voltages of each cell should remain close to one another. There should never really be more than 0.05v difference between the cells. When batteries are connected in series, the voltages will usually even out. When you see a battery like this, where there is a large voltage difference between cells (especially a new battery), it's safe to assume that one of the cells is faulty.
Jacob B
CC BY-SA 4.0
2020-11-15T02:02:58.477Z
Thank you for the clarification guys. Well I suppose I can salvage the individual lithium-ions? Including the one with 2.93v?
DroneDome
CC BY-SA 4.0
2020-11-15T07:42:54.413Z
Yes, you can probably salvage at least some of the individual lithium-ions. The one with 2.93v may not be salvageable if it has internal damage. But before tearing the battery apart, I highly recommend taking a picture of the battery's cell voltages and contacting the seller to see if they will replace it. (If you bought it from RaceDayQuads, they will probably be willing to replace it)
Jacob B
CC BY-SA 4.0
2020-11-15T14:31:22.730Z
@Jacob B, appreciate the advice. I shall do exactly that and reach out to racedayquads.com.
DroneDome
<batteries><charging>
Li-ion battery will not charge on ISDT Q8 Smart Charger
DroneDome
# Li-ion battery will not charge on ISDT Q8 Smart Charger

(Asked by: username_0 on 2020-11-15)

The Li-ion Pack has 4 18650 lithium-ion batteries with a soldered Balancer and XT60.
On my ISDT charger, the read out voltage for each battery cell is:

1. 3.17V
2. 3.18V
3. 3.29V
4. 2.93V

Whenever I try to charge the Li-ion Pack, I get:

* "This operation is not supported"

My Question:
How can I bypass this using my ISDT charger?

[Auline 14.8V 4S 18650 2600mAh](https://www.racedayquads.com/products/auline-14-8v-4s-18650-2600mah-1c-li-ion-battery-w-built-in-protective-board-for-dji-goggles-xt60?_pos=5&_sid=e633cb311&_ss=r)

[ISDT Q8](https://www.racedayquads.com/products/isdt-q8-500w-20a-charger?_pos=1&_sid=4f8e8dbb5&_ss=r)

**Tags:** batteries, charging
> **Comments:**
> **username_1**: Could you link to the product you're talking about? I haven't ever heard of the LionPack.  
> **username_2**: @ifconfig I believe it's a Lithium ion battery. I've seen both "Li-ion" and "lion" as abbreviations.  
> **username_0**: Sorry about that, I just added the product links.  
> **username_2**: @DroneDome it might not be charging because of a safety feature built into the charger. If there are cells with 3.17v and 2.93v in the same battery, that could mean there is a problem with one or more of the battery cells, which could be very dangerous. If the battery is new, I would recommend contacting the seller and asking if they can replace the battery.  
> **username_0**: @Jacob B, I thought you can discharge a lithium-ion as low as 2.5 - 2.7v and still be able to salvage it? And yes, the battery is new  
> **username_1**: @DroneDome, no that's not correct. Discharging below ~3.0 V/cell irreparably damages the cells.  
> **username_2**: @DroneDome yes, you can discharge a Li-ion to a voltage of ~2.8v or 3.0v, but in any series battery (lipo and Li-ion) the voltages of each cell should remain close to one another. There should never really be more than 0.05v difference between the cells. When batteries are connected in series, the voltages will usually even out. When you see a battery like this, where there is a large voltage difference between cells (especially a new battery), it's safe to assume that one of the cells is faulty.  
> **username_0**: Thank you for the clarification guys. Well I suppose I can salvage the individual lithium-ions? Including the one with 2.93v?  
> **username_2**: Yes, you can probably salvage at least some of the individual lithium-ions. The one with 2.93v may not be salvageable if it has internal damage. But before tearing the battery apart, I highly recommend taking a picture of the battery's cell voltages and contacting the seller to see if they will replace it. (If you bought it from RaceDayQuads, they will probably be willing to replace it)  
> **username_0**: @Jacob B, appreciate the advice. I shall do exactly that and reach out to racedayquads.com.  

---

## 1 answers

### Answer by username_3 on 2020-11-15. Score: 1

**Note: This answer does not consider whether this is a 'good idea', as there can be safety concerns with over-discharged lithium batteries (e.g. see [this question](https://drones.stackexchange.com/q/304/68).)**  
I aim here to address the 'how' of the question, but you must decide if you consider the risks acceptable (for this battery, or others in the future) and follow all the usual charging safety measures.

It looks like the charger in question supports unbalanced charging, so you may be able to set the battery to charge in unbalanced mode which should ignore the per-cell voltage. In this case, I would set the charge current as low as possible and charge somewhere very fireproof - in case the low cell voltage has caused damage - and plan to stop the charge once the faulty cell has exceeded about 3.1V. You should then be able to try balance charging again.

However, the charger may check the sum of the individual cell voltages for the unbalanced charging mode and could therefore still decide that the total voltage is too low.


---

