I completed the page explaining how I constructed rechargeable LiPo battery packs for Powered Up and Control+ hubs. See it here!
https://philohome.com/pupbat/pupbat.htm

@Philo, you did it again!

This is absolutely nice. Really cool.

Thank you very much!

All the best
Thorsten

Neat idea. Does the PUP and Control+ prevent the LiPO battery voltage from dropping too low?

 

Very good article and really??  10.5 volts input limitation that is the same as the IR setup !!!!  Buwizz are you reading this!!!   

Thanks all...

8 hours ago, dr_spock said:

Neat idea. Does the PUP and Control+ prevent the LiPO battery voltage from dropping too low? 

Unfortunately no. C+ hub should do that (it has a pin/switch to detect battery type) but it doesn't seem to be implemented in firmware. I guess it will be updated if/when LEGO provides a rechargeable battery. There is a chapter about that and other battery care considerations at the bottom of page.

6 hours ago, sirslayer said:

10.5 volts input limitation that is the same as the IR setup !!!

Same chip, same limitations... (low max voltage, low maximum current). OTOH, it is a really sturdy guy!

Edited January 29, 20205 yr by Philo

Really nice guide, thanks for this. Might be a stupid question, but how does it compare to using "normal" rechargeable 1.5v AAs? 

There is no hard and dry answer to this... As for capacity my LiPo solution is no match since you can easily find NiMH AA cells with 3 times the capacity. But LiPo has an edge for weight or maximum current. Also charging time is faster, and lifetime longer (if well handled)

Edited January 29, 20205 yr by Philo

14 hours ago, sirslayer said:

Very good article and really??  10.5 volts input limitation that is the same as the IR setup !!!!  Buwizz are you reading this!!

@Zerobricks

--

subject2

When I look into the battery compartment (not the cradle but the C+ box itself) I see a very small pushbutton.
It was allready mentioned that this might have something to do with a future official LiPo/LiOn battery.
I wonder what it does?
Accepting a lower voltage f.a. ?

Edited January 29, 20205 yr by JaBaCaDaBra

21 minutes ago, JaBaCaDaBra said:

I wonder what it does?
Accepting a lower voltage f.a. ?

It should change behaviour of firmware (thresholds):

- Report a better charge percentage (currently, 90% charge level is reported for a 1/3 charged LiPo)

- Shutdown hub below 6V or so to avoid overdischarge of batteries.

maybe you can take advantage of it

24 minutes ago, JaBaCaDaBra said:

maybe you can take advantage of it

I did add a pin pressing the switch, but it does nothing currently. Guess it needs a firmware update!

17 hours ago, sirslayer said:

Very good article and really??  10.5 volts input limitation that is the same as the IR setup !!!!  Buwizz are you reading this!!!   

We are, no worries . The 10,8V seems to be general limitation when dealing with low voltage controllers. But if you switch to a higher voltage controller, like ones for auto industry, than you have issues with low voltage control. It's hard to have the best of both worlds.

Buwizz with the Powered Up ports or even better Powered Up and PF ports on the same device!!... @Philo.. show them how to build one!!!!!  Please :) 

11 hours ago, sirslayer said:

show them how to build one!!!!! 

I'm sure they know how to do that technically. real issues are copyright/IP ones... and I'm not competent for that ;)

I'm wondering what battery percent data my app would show when you power such a hub with LiPo. Maybe I will check it out soon:)

Glad I found this post we had chewed through some regular  AA batteries Christmas. I did a rather simple mod using an existing lipo I use for my RC car it worked great. I used some crocodile leads to make the connections which is a bit crude and a little worried about shorting it if they come loose but work in progress and they seem secure. The battery mount needs some work but the lipo is light enough and mounted centrally which works. Now looking for a smaller battery ONe that fitted in the rear would be good. I have a friend looking to 3d print me the case. But mean time endless hours of fun with the new 4x4. Thanks, Philo for your work 

 

I know this is an old topic, but I have been working on this project for almost a year. So if anyone ever looks in, here's a picture of the developments and a link for a short intro video.

 

Wow! That is totally cool.

And this is what I was hoping TLG would do for long.

You have clearly demonstrated that this works: Rechargeable (LiPo) batteries, safely handled (I believe the electronics board is doing exactly that).

Now, there is one downside so far: How to charge the LiPo without disassembling the battery enclosure?

Thank you very much for sharing (the one-year development period is absolutely reasonable)

Best wishes,
Thorsten

3 minutes ago, Toastie said:

Wow! That is totally cool.

And this is what I was hoping TLG would do for long.

You have clearly demonstrated that this works: Rechargeable (LiPo) batteries, safely handled (I believe the electronics board is doing exactly that).

Now, there is one downside so far: How to charge the LiPo without disassembling the battery enclosure?

Thank you very much for sharing (the one-year development period is absolutely reasonable)

Best wishes,
Thorsten

Hi Thorsten,

Glad, you like it.

The electronics contains a charger circuit which works from USB3.1 port.

It’s just a prototype (currently I only have a 3d printed box), I’m looking for mass production opportunities.

Best wishes,

Gergo

Hi Gergo,

damned, I missed the location of that charging port. This does not get any better. This is how I see TLG should move forward. You did it.

Best,
Thorsten

Very well thought out! Would there happen to be an LED or something to indicate the charge status? Either way, that looks like a very nicely executed solution!

Bit of the specs:

- Integrated 2 cell LiPo USB charger and power path management IC

- one green LED for charge indication

- The charger is set to a maximum current of 1 A, but can adapt the charging to the capabilities of the USB power supply

- charger has battery temp sensing in charge, thermal regulation and shutdown

- The user can choose with a small switch if the output boost converter is on (it is like a corded working mode) or turned of while the Battery is charging

- 10 A capable boost converter on the power out side configured to produce 9V 3A continuous output

The Battery safety electronics is in the battery pack and has overcharge, over discharge, under-voltage shutdown capabilities (it is a cheap but efficient Chinese BMS electronic)

 

Sounds good, I really hope you find a production partner!

What's the projected selling price?

1 hour ago, amorti said:

Sounds good, I really hope you find a production partner!

What's the projected selling price?

It depends on the injetion molding costs the PCB price and the packaging. I plan to keep the price between 50 to 100 US dollars but it is without battery to be able to send overseas easily. But I also plan to provide a very detailed instruction for Battery creation from locally available parts.

@Phondly - Great job, congratulations!

Edited January 21, 20223 yr by Philo