Mavic Air 2 - Extended capacity battery mod - 7350mAh - Not my work

[lee82gx]

I suppose there is limited English reviews of this mod.

In Malaysia and several countries in South East Asia, some skilled modders have access to raw DJI battery cells (through China).

By combining this with the existing cells you can have 3S2P configurations, for around US$70 you can modify your existing battery pack.



Here is how it performs:

Hover to 0 - 43:42s
Short flight to 9% (Auto Landing begins), no cancellation allowed - 40:28s (I spent a good 3 mins on the ground to check everything and lock gps)

Dat files to check the flight parameters:
A few notes - Battery capacity was reprogrammed to 7350mAh, and so it is intelligent. You can see the remaining cap in mAh, and also % tracking it closely. RTH time is also accurate. But the dat file is somehow truncated in this file and it only records up to 1840s. Another roughly 10mins of flight was not recorded somehow...

Battery current is around 10A, flying very steadily and was around 2-5m/s speed. Motor speed on Front ard 7200rpm. ESC temp "~630", I assume is 63C. After land, the motor covers, arms, motors do not feel too hot to touch. They are definitely warmer than normal. As comparison, I previously tested Mavic Pro with extended batteries and they are so much warmer.



I just compare a normal standard battery in a normal flight.
Battery current is around 6.6A, flying very steadily and was very low speed. Motor speed on Front ard 6400rpm. ESC temp "~540", I assume is 54C. After land, the motor covers, arms, motors feels only slightly warm. Battery temp here is 47C


Based on the increase in load 10A vs 6.6A, the flight times are pretty makes sense. 7.35Ah/10A=44min. 3.5Ah/6.6A=32min

Lastly the weight is 390g total. So if you have a payload of about 150g, then the flight time will decrease to 21mins.

 

[Nonprophet]

Why? Seriously. Why risk damage to a $1,000 drone and voiding your warranty when we average 25 minutes per flight flying it the way they were intended......

 

[lee82gx]

Why? Seriously. Why risk damage to a $1,000 drone and voiding your warranty when we average 25 minutes per flight flying it the way they were intended......

Hello, i detailed a long post with the intention talking about risk management to my own drone, I believe it was an acceptable level. Many of the posts in this subsection of the forum voids warranty and present some form of additional risk or another.

 

[gb160]

Why? Seriously. Why risk damage to a $1,000 drone and voiding your warranty when we average 25 minutes per flight flying it the way they were intended......

Because some of us just want to see the world burn.

 

[lee82gx]

Actually, with the new task list 45 point hyperlapse. I plan to do some aerial mapping and surveying. If you tried it, a 2x20min flights with waypoints stitched in between is a pain in butt to map. That was my original intention.

With a 40min battery, you can do a much larger area.

 

[GadgetGuy]

Actually, with the new task list 45 point hyperlapse. I plan to do some aerial mapping and surveying. If you tried it, a 2x20min flights with waypoints stitched in between is a pain in butt to map. That was my original intention.

With a 40min battery, you can do a much larger area.

I believe you can now pause and resume a waypoint mission while swapping batteries in between. No need for a continuous flight any more.

 

[lee82gx]

I believe you can now pause and resume a waypoint mission while swapping batteries in between. No need for a continuous flight any more.

I gotta try this....

 

[Dr. Bill 1969]

I suppose there is limited English reviews of this mod.

In Malaysia and several countries in South East Asia, some skilled modders have access to raw DJI battery cells (through China).

By combining this with the existing cells you can have 3S2P configurations, for around US$70 you can modify your existing battery pack.

View attachment 110572

Here is how it performs:

Hover to 0 - 43:42s
Short flight to 9% (Auto Landing begins), no cancellation allowed - 40:28s (I spent a good 3 mins on the ground to check everything and lock gps)

Dat files to check the flight parameters:View attachment 110576
A few notes - Battery capacity was reprogrammed to 7350mAh, and so it is intelligent. You can see the remaining cap in mAh, and also % tracking it closely. RTH time is also accurate. But the dat file is somehow truncated in this file and it only records up to 1840s. Another roughly 10mins of flight was not recorded somehow...

Battery current is around 10A, flying very steadily and was around 2-5m/s speed. Motor speed on Front ard 7200rpm. ESC temp "~630", I assume is 63C. After land, the motor covers, arms, motors do not feel too hot to touch. They are definitely warmer than normal. As comparison, I previously tested Mavic Pro with extended batteries and they are so much warmer.

View attachment 110578

I just compare a normal standard battery in a normal flight.
Battery current is around 6.6A, flying very steadily and was very low speed. Motor speed on Front ard 6400rpm. ESC temp "~540", I assume is 54C. After land, the motor covers, arms, motors feels only slightly warm. Battery temp here is 47C


Based on the increase in load 10A vs 6.6A, the flight times are pretty makes sense. 7.35Ah/10A=44min. 3.5Ah/6.6A=32min

Lastly the weight is 390g total. So if you have a payload of about 150g, then the flight time will decrease to 21mins.

Neat modification. As to the naysayers, there's no substitute for more lingertime.

 

[lupedj4]

QUestion, How do you program the BMS (Or Smart battery controller) to think that the battery has a higher capacity and what program you used to reprogrammed? cause i did that to mine drone but as if it loosing flight time and when it hit 0, i still have power to fly the drone

 

[lee82gx]

A few things before I explain further.
1. It’s not my work, as stated in title.
1.1 whatever I say next is based on my theory and not practice...
2. Battery communicates via SMB protocol ( system management bus).
You need to have a Ev2300 or compatible board, with drivers to read And decode the SMB data. It consist of SDA, SDC and GND pins. Sourcing for this is not difficult if you are willing to pay.
3. To read or write the PROM on the BMS you also need developer level access, which is possible if you have UBRT with read write access, or BQ studio with developer access to unseal or unlock the ROM for reprogram. Both can allow you to rewrite the internal capacity to any other value you desire. I am neither and trying to source for this seems expensive
4. Your hardware hack looks neat. But you have to do proper 3S2P for a good function. From the pictures you look like just wired 3S1P + 3S1P, whereby the you paralleled 2 11.4V packs. That can also work but the packs are not always in good voltage balance. One pack may be higher than the other.
5. Of course if you do 4, the BMS will never charge properly or even if you manage to set it to a higher cap, it does not discharge properly along with the capacity curve.
For some years, your method of strapping a parallel pack is the normal way to boost capacity, so I’m not sure why it’s not working in your case. Are you sure you wired correctly?

you need to charge the extra pack by yourself externally with a RC charger, by balance charging preferably. Then with your fully charged original battery on the drone and powered up, only after that you attach the external pack to the Drone’s + and - points or to the battery’s output terminal. It should work in extending the extending the flight time. the voltage curve should drop very slowly as intended and flight time should increase, but I’ve not tried this with Mavic Air 2. Last I tried was with a Mavic pro 1.

 

[Craig Notts]

I suppose there is limited English reviews of this mod.

In Malaysia and several countries in South East Asia, some skilled modders have access to raw DJI battery cells (through China).

By combining this with the existing cells you can have 3S2P configurations, for around US$70 you can modify your existing battery pack.

View attachment 110572

Here is how it performs:

Hover to 0 - 43:42s
Short flight to 9% (Auto Landing begins), no cancellation allowed - 40:28s (I spent a good 3 mins on the ground to check everything and lock gps)

Dat files to check the flight parameters:View attachment 110576
A few notes - Battery capacity was reprogrammed to 7350mAh, and so it is intelligent. You can see the remaining cap in mAh, and also % tracking it closely. RTH time is also accurate. But the dat file is somehow truncated in this file and it only records up to 1840s. Another roughly 10mins of flight was not recorded somehow...

Battery current is around 10A, flying very steadily and was around 2-5m/s speed. Motor speed on Front ard 7200rpm. ESC temp "~630", I assume is 63C. After land, the motor covers, arms, motors do not feel too hot to touch. They are definitely warmer than normal. As comparison, I previously tested Mavic Pro with extended batteries and they are so much warmer.

View attachment 110578

I just compare a normal standard battery in a normal flight.
Battery current is around 6.6A, flying very steadily and was very low speed. Motor speed on Front ard 6400rpm. ESC temp "~540", I assume is 54C. After land, the motor covers, arms, motors feels only slightly warm. Battery temp here is 47C


Based on the increase in load 10A vs 6.6A, the flight times are pretty makes sense. 7.35Ah/10A=44min. 3.5Ah/6.6A=32min

Lastly the weight is 390g total. So if you have a payload of about 150g, then the flight time will decrease to 21mins.

Nice info my friend. These figures are about what was quoted

 

[netfolks2000]

The time will come, hopefully soon, that we'll get all that extra capacity in the same size format as battery technology advances. I can accomplish all my missions, however, in the time we have now. At maximum the tech changes so fast that any drone is obsolete within two years as it is. In fact, I look daily for new stuff, news, rumors, evidence of advancement.

 

[marchos77]

I would be interested to know how much heavier this makes the drone? How much more strain there is on the motors having to carry the extra weight? I like the idea don't get me wrong, but if you are putting a ton more strain on the motors to keep it in flight, there is a risk there. Unfortunately, loosing 1 motor on these things brings it down.

 

[Korrd]

I suppose there is limited English reviews of this mod.

In Malaysia and several countries in South East Asia, some skilled modders have access to raw DJI battery cells (through China).

By combining this with the existing cells you can have 3S2P configurations, for around US$70 you can modify your existing battery pack.

View attachment 110572

Here is how it performs:

Hover to 0 - 43:42s
Short flight to 9% (Auto Landing begins), no cancellation allowed - 40:28s (I spent a good 3 mins on the ground to check everything and lock gps)

Dat files to check the flight parameters:View attachment 110576
A few notes - Battery capacity was reprogrammed to 7350mAh, and so it is intelligent. You can see the remaining cap in mAh, and also % tracking it closely. RTH time is also accurate. But the dat file is somehow truncated in this file and it only records up to 1840s. Another roughly 10mins of flight was not recorded somehow...

Battery current is around 10A, flying very steadily and was around 2-5m/s speed. Motor speed on Front ard 7200rpm. ESC temp "~630", I assume is 63C. After land, the motor covers, arms, motors do not feel too hot to touch. They are definitely warmer than normal. As comparison, I previously tested Mavic Pro with extended batteries and they are so much warmer.

View attachment 110578

I just compare a normal standard battery in a normal flight.
Battery current is around 6.6A, flying very steadily and was very low speed. Motor speed on Front ard 6400rpm. ESC temp "~540", I assume is 54C. After land, the motor covers, arms, motors feels only slightly warm. Battery temp here is 47C


Based on the increase in load 10A vs 6.6A, the flight times are pretty makes sense. 7.35Ah/10A=44min. 3.5Ah/6.6A=32min

Lastly the weight is 390g total. So if you have a payload of about 150g, then the flight time will decrease to 21mins.

Excellent info.

Did you conduct any tests related to wind resistance?
Since this mod increases the drone’s surface area, I wonder how much it is affected by that.

 

[Craig Notts]

Excellent info.

Did you conduct any tests related to wind resistance?
Since this mod increases the drone’s surface area, I wonder how much it is affected by that.

You can talk about wind resistance I suppose but the fact remains that I can fly out to 10 km ,so 20 km round trip and still land with 25 % battery remaining

 

[Craig Notts]

I would be interested to know how much heavier this makes the drone? How much more strain there is on the motors having to carry the extra weight? I like the idea don't get me wrong, but if you are putting a ton more strain on the motors to keep it in flight, there is a risk there. Unfortunately, loosing 1 motor on these things brings it down.

The motors handle the extra weight fine . Even with the extra battery , this is nowhere near as heavy as as a mavic 2 pro

 

[lee82gx]

Excellent info.

Did you conduct any tests related to wind resistance?
Since this mod increases the drone’s surface area, I wonder how much it is affected by that.

Yes, top speed remains the same in all directions. 12m/s N mode and 19m/s S mode.

 

[lee82gx]

I would be interested to know how much heavier this makes the drone? How much more strain there is on the motors having to carry the extra weight? I like the idea don't get me wrong, but if you are putting a ton more strain on the motors to keep it in flight, there is a risk there. Unfortunately, loosing 1 motor on these things brings it down.

I remember around 100g or so. The risks are obvious. What is not obvious is what limits do we actually have. How will we know if we don't test? I suppose even DJI themselves do not know until they test. Apparently I've finished around 15 flights without a hiccup.

How long before its declared "safe" and is it ever ?
All I know is I can achieve something very uncommon, perhaps my drone will not last 10 years.

 

[subseageorge]

I suppose there is limited English reviews of this mod.

In Malaysia and several countries in South East Asia, some skilled modders have access to raw DJI battery cells (through China).

By combining this with the existing cells you can have 3S2P configurations, for around US$70 you can modify your existing battery pack.

View attachment 110572

Here is how it performs:

Hover to 0 - 43:42s
Short flight to 9% (Auto Landing begins), no cancellation allowed - 40:28s (I spent a good 3 mins on the ground to check everything and lock gps)

Dat files to check the flight parameters:View attachment 110576
A few notes - Battery capacity was reprogrammed to 7350mAh, and so it is intelligent. You can see the remaining cap in mAh, and also % tracking it closely. RTH time is also accurate. But the dat file is somehow truncated in this file and it only records up to 1840s. Another roughly 10mins of flight was not recorded somehow...

Battery current is around 10A, flying very steadily and was around 2-5m/s speed. Motor speed on Front ard 7200rpm. ESC temp "~630", I assume is 63C. After land, the motor covers, arms, motors do not feel too hot to touch. They are definitely warmer than normal. As comparison, I previously tested Mavic Pro with extended batteries and they are so much warmer.

View attachment 110578

I just compare a normal standard battery in a normal flight.
Battery current is around 6.6A, flying very steadily and was very low speed. Motor speed on Front ard 6400rpm. ESC temp "~540", I assume is 54C. After land, the motor covers, arms, motors feels only slightly warm. Battery temp here is 47C


Based on the increase in load 10A vs 6.6A, the flight times are pretty makes sense. 7.35Ah/10A=44min. 3.5Ah/6.6A=32min

Lastly the weight is 390g total. So if you have a payload of about 150g, then the flight time will decrease to 21mins.

Do you have a contact for getting them in Malaysia ?

 

[lee82gx]

Do you have a contact for getting them in Malaysia ?

Hi, Yes of course. I have 3 contacts, 1 in Perak (central peninsula), 1 in KL (Capital) and 1 in Kedah (Northern). Which would you like? You can PM me.