Bosch Solar Charging

Sunpower makes the panels themselves, which are being used in foldables by many brands. However, they are not thin-film solar, so they weigh more, are typically larger, will break if dropped or mistreated and have poor performance in low light and in partial shading conditions
 
This was the only local trusted company option available to me at the time:

That's US$1,710.00 each :)
I'm kind of glad i paid the expensive US to Australia freight, the Customs Clearance fee & our GST.
The P3-125's do work ok, lightweight and each fit in one of my front panniers.
 
I just received the P3Solar charger in the mail today, and thought I'd share my initial impressions.

The material is definitely thinner and lighter than the MiaSole charger (my p3-125w weighs 3.5lbs or 1.59kg, which is less than webcurl's one). However, it seems rough around the edges. It feels like a spongy, plasticized cardboard is used for the backing. I'm sure it will prove durable... it just feels wrong and is ugly in an industrial way. While the Baijian solar charger folds up neatly and compactly, this one reduces in depth by more than two thirds its total while compressed, then springs back when let go. Ahh well.

I like how it has a front pouch. I can store my MPPT and cables / alligator clips in there. Also, while I haven't had a chance to test it yet, I am happy to report that the device has its rated maximum-power-point voltage and current stated as being 31V/4.8A, which is in line with the newer data sheets (the older ones state 30V/4.4A) that suggest a 150W power output.
 

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I'm sure it will prove durable... it just feels wrong and is ugly in an industrial way. While the Baijian solar charger folds up neatly and compactly, this one reduces in depth by more than two thirds its total while compressed, then springs back when let go. Ahh well.
It get's softer and more pliable the more you use/own it.
 
Most modern power supplies convert 115 -230VAC to DC via rectifier then use DC-DC nverter to isloate and drop recitified mains voltage to a working voltage for charger. This is likely to be around 40VDC which is used to charge battery directly.
Because of main rectification they don't care about shape of input sinewave unlike AC motors.
In theory could modify a mains 2A charger by using a 12VDC-40DCV inverter to feed secondary of charger. Really depends on how smart inverter part of charger is and if it talks to charger smarts.
 
Most modern power supplies convert 115 -230VAC to DC via rectifier then use DC-DC nverter to isloate and drop recitified mains voltage to a working voltage for charger. This is likely to be around 40VDC which is used to charge battery directly.
Because of main rectification they don't care about shape of input sinewave unlike AC motors.

Thanks, never thought of it like that b4.
So in theory all Modified Sine Wave inverters should be fine with all switch mode power supplied electronics.

In theory could modify a mains 2A charger by using a 12VDC-40DCV inverter to feed secondary of charger. Really depends on how smart inverter part of charger is and if it talks to charger smarts.

Yes, i've got a broken 2A Bosch charger and have noticed a trace from output DC section to the input AC section, possibly a temperature protection or other setup?
 
Thanks, never thought of it like that b4.
So in theory all Modified Sine Wave inverters should be fine with all switch mode power supplied electronics.



Yes, i've got a broken 2A Bosch charger and have noticed a trace from output DC section to the input AC section, possibly a temperature protection or other setup?
Could be feedback for voltage control. Driver on mains side needs to know when secondary is at 40V. Some circuits use optocoupler to maintain electrical isolation.
There should be transformer isolating primary (mains) and secondary.
 
It would be easier and better to charge from your alternator if possible..

Solar is not efficient , the world is figuring out.
 
Solar charging Bosch ebike batteries seems to be pretty easy.
Here are some pictures from my first test connected to a 100W folding panel. Works well. This should fully charge a 500Wh battery on a sunny day. I will test it on the next camping trip.
I did now cut the Bosch ebike charger cable and added a connector. So I can use the original plug with the solar panel and still with the charger.
It would even be possible to charge two batteries at the same time (with the correct wiring). That way I could just use a 50W panel and have two 500Wh batteries fully charged in a week. I could hide a weather proof box with two batteries and the charge controller somewhere in the woods where there is some sun and set up a 50W solar panel. Then I could just swap batteries on a weekend camping trip anywhere.
In that bag on the last picture is my 1kWh Bosch battery (60 cells 21700). With 4.4kg the solar charging setup weighs about the same as my 1kWh battery.
BoschSolar1.jpg
BoschSolar2.jpg
BoschSolar3.jpg
BoschSolar4.jpg
BoschSolar5.jpg
 
Solar charging Bosch ebike batteries seems to be pretty easy.
In that bag on the last picture is my 1kWh Bosch battery (60 cells 21700). With 4.4kg the solar charging setup weighs about the same as my 1kWh battery.
Great stuff!
You have a non-Bosch 1kWh 60 cell 21700 battery working with a Bosch ebike eco-system?
Any of those AMP SuperSeal connectors getting slightly warm at all (connector pins or crimp)?
If so, i'd suggest Amass XT60 connectors instead, much better connection = lower loss of current.
Also, if you can afford a Genasun boost MPPT controller then i think you'll find some major efficiency gains over the MPT-7210A or maybe even a cheaper equivalent:
 
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You have a non-Bosch 1kWh 60 cell 21700 battery working with a Bosch ebike eco-system?
Yes. I was able to repair some Bosch BMS from dead batteries I got in the past. They work just fine with any 10s*p.
With the dual battery setup I always ride with 1,500Wh which is enough for a weekend camping trip.

Any of those AMP SuperSeal connectors getting slightly warm at all (connector pins or crimp)?
No. It's less then two Amps, so no problem at all. I modified the connection with the 36V to USB, in the picture it was still for the testing.

i'd suggest Amass XT60 connectors instead
I like these Dorman connectors much better. Don't need heavy duty wires and they are much easier to connect and disconnect.
I also have the 2-pin connector on the 1kWh battery so I can connect a 20W 12V heatpad (for pets) for cold nights. Keeps me nice warm in freezing temperatures.

I already ordered it a while ago. Still waiting for it to arrive.

Genasun boost MPPT controller
I like the MPT-7210A so far. Nicely displays all the data I need. Just the fan might be annoying, but I can replace that. And I can connect it to any power source as it also is a DC-DC converter.
I don't think the Genasun is worth the extra $ for that little more efficiency.

BTW, the 100W folding solar panel was only $180. Too bad they are sold out. The USB board (for the 5V signal to turn the battery on) was only $3.

I also bought some SunPower solar modules before they getting too expensive or sold out. They will be for my ebike camping trailer project.
 
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FYI, had a few beers with a good mate (Aussie for friend) of mine, he comes from Laufen...

Yes. I was able to repair some Bosch BMS from dead batteries I got in the past. They work just fine with any 10s*p.

Am i to assume that the BMS was from a pre-powerube battery without a propitiatory (Oval shapee) Bosch connector?
I ask as i've read on the pedelecforum.de somewhere that newer Bosch BMS's can brick themselves if there's a loss of any standby power, but as i assume you know accurate information about these Bosch things is hard to come by.
And you have both Positive & Negative from the USB output going to the battery input - positive to the CAN bus conductor & negative connected to the other negative?

I like the MPT-7210A so far. Nicely displays all the data I need. Just the fan might be annoying, but I can replace that. And I can connect it to any power source as it also is a DC-DC converter.
I don't think the Genasun is worth the extra $ for that little more efficiency.

The MPT-7210A's flexibility is certainly handy!
 
FYI, had a few beers with a good mate (Aussie for friend) of mine, he comes from Laufen...
👍

BMS was from a pre-powerube battery
Yes, mine are all from frame packs. They are easier to use with self made battery packs. And I only use the frame batteries anyway.
I have a brand new 625 PowerTube but nobody wants to buy it. I might use it with the trailer later if I ever build one.

And you have both Positive & Negative from the USB output going to the battery input - positive to the CAN bus conductor & negative connected to the other negative?
Correct.
 
👍


Yes, mine are all from frame packs. They are easier to use with self made battery packs. And I only use the frame batteries anyway.
I have a brand new 625 PowerTube but nobody wants to buy it. I might use it with the trailer later if I ever build one.


Correct.

Appreciate the rare Bosch information!
Have you tried charging a powertube with that setup, on-bike and off?
 
Have you tried charging a powertube with that setup, on-bike and off?
That will work. Just like you can charge them with the 4A and 2A chargers.
Over the weekend I will try charging with 6A from solar. A nice feature of the MPT-7210A is that you can set a maximum current.
 
That will work. Just like you can charge them with the 4A and 2A chargers.
Over the weekend I will try charging with 6A from solar. A nice feature of the MPT-7210A is that you can set a maximum current.
@ 26:15 :

Also, i think the Bosch 6A charger has a 4th conductor, this is all i know about that :)
And i'm curious about their "New System" regarding charging, etc. as it has a different, new connector and the system uses the newer CAN FD bus.
 
@ 26:15 :

Also, i think the Bosch 6A charger has a 4th conductor, this is all i know about that :)
And i'm curious about their "New System" regarding charging, etc. as it has a different, new connector and the system uses the newer CAN FD bus.
The 6A charger "talks" to the battery to check if it has the 6A software.
The batteries can also talk to each other. I will build another cable where I can plug in my charger and two batteries. For the charger it needs the 5V signal to wake the battery up. Between the batteries it needs the power and CAN bus and then the batteries take turns with charging every 10% or so.

Speaking of 6A chargers, you can get a cheaper real 6A 110V charger for Bosch here:
I was thinking of ordering one, but I just stick with the 4A chargers and my solar charging.

BTW This is my favorite when it comes to the batteries
IMG-20210429-WA0003.jpg
 
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