Bamboo GT AT 50km Range Project

Bns = BMS

 

Now I've got everything for second edition portable charger- I've found a car charger with wide input voltage which will be using 6s BMS straight to 42vdc.

 

Eugene
looking good
yeah decided that if I am going for a new enclosure I should max out battery capacity to reduce individual cell demand and hence max out Ah on MJ1s.
my cells should arrive tomorrow -still waiting on the nickel strip to turn up.
I think the nickel strips that come with the welder are nickel coated steel .tested them by scuffing and salt water immersion testing showed rust after 48 hours. not sure if it is a major issue in your case as you are using them as belts and braces to the wider strips that will carry most of yhe current
What are you using for the serial connections ?
Cheers

 

I do have a few 6s batteries in my disposal.. 6 x 5800ah, 2 x 8000ah, 2 x 22000mah just pretty much doing nothing. So, I thought a portable charger is a good use for it)

 

Thanks mate- I totally agree with you - 8p mj1 is going to be a rock!!!

I've ordered flat 16mm(Sq) copper cable for serial connections. I hope will do, otherwise I have bunch of 8awg silicone wires lying around. I can double those up as well..

 

Eugene
car charger looks interesting .do you a supplier link
Cheers

 

I've been looking for it for a while. I've found a few bulky (larger units) options for around $140 incl postage from bike shops. Wasn't happy with any of them.
But then I came across this company on Alibaba . Unfortunately their min ordered is 100 units for approx $40 per unit plus delivery. So for now I've requested just one sample through my company. Had to pay dhl courier to get it delivered. So total price wasn't great in the end ...

 

Yep, those strips looked very suspicious- and I've used them just to reinforce welding spots. As 8 x 2 strips I have look a bit too thick for that welder. I'd say on max settings 1.5 thickness probably is max I would recommend using. Mine welding spots are fine but I do 3-4 double shots to each spot. And welder gets to hot pretty quickly.

 

MJ1 cells have arrived -very nice
Tried a stick on paper insulator on top of cell +v but dont think I will need them as the MJ1 already has a circular insulator which will do the job
Next step is to start building the 8 cell battery packs

 

Looking good! Yep, I don't think you need additional insulator or extra heat shrink wrapping which you were going to do on each cell.

 

I'm slowly progressing with mine project as well. All 5 packs (2S4P) are ready now for assembling them in series. But while I'm waiting for a connector for a balance plug I've started second test. Using iCharger 1010+ I've balanced each pack to full than Cycle at 4A :
From 4.2V - Discharge to 3.3v charge back to 4.2v - I'm getting average 9868Mah with IR 6ohm per 4P pack.
So looks like I'll have useful 10Ah. Will be interesting to see how it will perform against stock 10Ah Carbon GT. My average range on 8" AT was about 22Km..

 

Hi Eugene
Wondering if you managed to spot weld 4 nickel strips ? or if your config/design is only 2 strips max
I am having trouble getting four to stick so may have to change my design to limit to two strips going along both sets of 4 cells and then multiple cross strips a bit like yours to parellell up the 8 cells. this would mean 3 strips thick for some welds ( or solder)
my nickel strip is 0.15 mm thick
Cheers

 

Hi Mate,
I've used 4 strips: 8mm x 0.2 plus the once which comes with welder itself. I've used Max settings on welder: 99/2/spring on top to max as well. With 8 x 0.2 strip I've done 2 shots to each spot (makes it 4 pulses to each spot in total). Once 8mm strips were in place, I've doubled everything up on top using just single shot still on 99/2. After just doing 1s4p pack welder was overheating and I could see some smoke (more likely just glue on the coils). So it was very long processes - stretching to a few days.

I hope that helps..
Cheers

 

Hi Guys,
Back to Balancing plug connector for evolve BMS - I've received my order today which was supposed to be: zh 1.5 11p. Unfortunately it's way too small. See pics.
Do you guys know if this is a correct zh 1.5 11p and seller simply sent me a wrong item? Or Evolve doesn't use zh 1.5 11p..

Any input will be much appreciated!

 

I've measured the distance between pins of those connectors: looks like it's 1.5mm
While on Evolve BMS distance is 2.0mm and standard Lipo balancing plugs is 2.5mm

I'll order zh 2.0 11p

 

I couldn't find a place to buy exactly the same plug as on BMS. It appears that a correct name for it is: JST tp/fp 2.0mm 11-pin
The only thing which looks close enough was JST PH 2.0mm 11-pin - found it on AliExpress. It should fit but it's not exactly the same plug.

Has anyone found a correct balance plug ?

 

Eugene

Ali express have a 12V to 42 charger with no minimum order qty - only 1.5A though

I have ordered one - see how it works

Cheers

Input 12V Car Charger Output 42V 1.5A DC Li ion battery charger charger Used for 36V lithium battery charging 5.5*2.1mm-in Chargers from Consumer Electronics on Aliexpress.com | Alibaba Group

 

Back to my battery project
I intend to in-build a few things that are simple to do and very low cost as bits are sourced from China

1) A warning horn for pedestrians - have sourced a very small 12V 1A horn to fit either under board or in battery enclosure - powered by a 35V/12V DC/DC regulator with feed from main battery via fuse . Have sourced a very simple 2 channel wireless remote control with relay output so I can sound horn via remote carried in left hand. Can vary the sound level of horn by either varying regulator output voltage or muffling horn with rags etc.

2) A double USB socket on outside of battery enclosure - powered by a 35V/5-5V DC/DC regulator with feed from main battery via fuse . this can be used to charge remote , phone and anything else that can charge from USB 5V supply

3) Front head-lights and rear red light - again powered from by a 35V/8V DC/DC regulator with feed from main battery via fuse . The wireless remote for horn has two channels so may use the second channel to switch on lights or have a separate switch.

Just had a thought that for the 2 channel remote - one button could be for a loud horn sound and the other could be a softer sound for when you are right up behind a pedestrian . Easy to do .

4) Voltage display on battery enclosure - something like
Battery Capacity Tester Indicator 12V 24v 48v car Lead acid batteries lithium #S018Y# High Quality-in Battery Testers from Home Improvement on Aliexpress.com | Alibaba Group

Link for DC/DC Converter

DC DC Buck Converter KIT Adjustable Power Supply DC DC Step Down Adapter 3A LM2596HVS LM2596HV Step Down Power 4.5 50V To 3 40V-in Integrated Circuits from Electronic Components & Supplies on Aliexpress.com | Alibaba Group

Cheers

 

Looks good! I've either missed it or it wasn't available half a year ago when I've purchased mine.

Thanks for the info!