Hobby king multi star on offer

[cwah]

Just to summarise for those who don't want to read it all...

All 1000wh battery of...
- multistar cost £218 and weight 5.5kg
- ncr18650pf cost £197.8 and weight 4.5kg
- ncr18650b cost £205.33 and weight 3.9kg!

 

[Kinninvie]

Then add the cost of a welder and cell holders and all the strips to join them together and of course the technical knowledge to actually build one safely.

Lipo are not unsafe when handled properly,just like petrol in a car,if you mistreat it then it can hurt you.

 

[cwah]

The welder do cost and I bought one....
But cell holder i don't use them anymore it takes too much space. I glue them with separator on cell group for chaffing risk.
The strip does almost cost nothing once you get some.

Like lipo, there is a cost to get started (lipo you need balance charger....), but once done, it saves time, money and space.

My ncr18650pf pack of 196 cells made last year hasn't been balanced a single time.... and i use it daily

 

[cwah]

I've got rid of all my lipo (zippy compact battery and cheap 4s turningy) more than a year ago and never regretted it.

- no more spagetthi wiring
- no more jst paralleling and cell log constant check
- no more cutting all the plug from a new battery pack to connect to new ones
- no more balance charging
- no more fear of fire at work while charging
- no more fear to that any small shock may damage the pack and cause fire
- no need hard case to protect the battery and apply compression

Even without the price benefit, the gravimetric density benefit and the higher lifecycle benefit I would prefer the 18650.

 

[dazza22345]

I think its more of the building it part that puts most of us off. Especially when there's a chance of burning the house down.

 

[derf]

The welder do cost and I bought one....
But cell holder i don't use them anymore it takes too much space. I glue them with separator on cell group for chaffing risk.
The strip does almost cost nothing once you get some.

Like lipo, there is a cost to get started (lipo you need balance charger....), but once done, it saves time, money and space.

My ncr18650pf pack of 196 cells made last year hasn't been balanced a single time.... and i use it daily

would it be possible to say where you get the strips cwah and what gluing cells together with a separator involves? I need to build a compact 48V battery and this sounds great, if it will work and survive potholes...

 

[cwah]

I'm doing it cheap and initially wanted to buy chafing tape but ended up using electric tap. What I do:
- use standard glue gun to stick cell group together
- then use electric tape to protect the cell group from chafing against the other group
- then protect with electric tape
- cover the complete pack with ren-forced tape
- waterproof it with food wrap
- protect the whole with tarpaulin
- apply compression with long jubilee clip

It doesn't add much weight but has been very good at protecting the pack that has been taking in and out every day to charge at work!

Tarlaulin skin starts to show sign of wear so I'd need to change it at some point!

 

[derf]

I'm doing it cheap and initially wanted to buy chafing tape but ended up using electric tap. What I do:
- use standard glue gun to stick cell group together
- then use electric tape to protect the cell group from chafing against the other group
- then protect with electric tape
- cover the complete pack with ren-forced tape
- waterproof it with food wrap
- protect the whole with tarpaulin
- apply compression with long jubilee clip

It doesn't add much weight but has been very good at protecting the pack that has been taking in and out every day to charge at work!

Tarlaulin skin starts to show sign of wear so I'd need to change it at some point!

many thanks. That sounds very brave though - a bit like something the sole survivor from fallout 4 might do. I suspect I need something more fastidious than food wrap, tarpaulin etc - but does it survive bumps and shocks etc?

 

[awol]

Say it takes 2 hours to charge your batteries and you set off at 8am.
\simply connect the batteries to your charger on the evening and set the timer to switch it on at 5.50am and off 2 hours later.
Then just unplug and away you go

What charger have you got? Both mine need me to press buttons like 'set' 'check' confirm' etc to start charging and I like your idea.

 

[Kinninvie]

What charger have you got? Both mine need me to press buttons like 'set' 'check' confirm' etc to start charging and I like your idea.

I use a pair of Meanwell NES350-48 power supplies in parallel to charge at 17.6 Amps..
They start when plugged in and taper off to virtually zero when the batteries are full.
I also have a pair of 24 volt Meanwells so if I need all 6 batteries for a ride I connect 4 to the 48s and the other 2 to the 24s and they are all done at the same time.

 

[cwah]

many thanks. That sounds very brave though - a bit like something the sole survivor from fallout 4 might do. I suspect I need something more fastidious than food wrap, tarpaulin etc - but does it survive bumps and shocks etc?

Good quality tarpaulin is a surprisingly strong material I'll definitely reuse. I have great success with and even made a bag for my battery out of tarpaulin.

I've just added food wrap few days ago because after a 6 months inspection everything was good but some areas of the pack started to rust dur to water leak.

 

[awol]

I use a pair of Meanwell NES350-48 power supplies in parallel to charge at 17.6 Amps..
They start when plugged in and taper off to virtually zero when the batteries are full.
I also have a pair of 24 volt Meanwells so if I need all 6 batteries for a ride I connect 4 to the 48s and the other 2 to the 24s and they are all done at the same time.

Yes very different to my chargers.
How/how often do you do the balancing or is it not needed all the time?

 

[Kinninvie]

Yes very different to my chargers.
How/how often do you do the balancing or is it not needed all the time?

If you dont discharge below 3.6V you wont need to balance them.
Just check them with a cell checker daily.
There is less than 10% capacity left below this level anyway.

 

[awol]

If you dont discharge below 3.6V you wont need to balance them.
Just check them with a cell checker daily.
There is less than 10% capacity left below this level anyway.

Would I be able to charge my 10s 6600mah pack up with my 2a charger I currently plug into my 36v bottle battery,first changing the plugs ?

 

[Nealh]

Kinninvie just to clarify to charge the 4 MS's off the paralleled PSU's (Meanwell's) , I assume the MS's are plugged into a parallel/balance board via the watt meter and then connected to the DC/ output side of the 2nd PSU. Do you use them as they are out of the box or have you done any mods to them at all as on ES ?

 

[cwah]

The DIY battery pack working for almost a year now...

It's not looking too bad. I had someone who told me it looks like a lady bag

 

[Kinninvie]

Would I be able to charge my 10s 6600mah pack up with my 2a charger I currently plug into my 36v bottle battery,first changing the plugs ?

ONLY if the output from that charger is between 41 and 42 volts.
You need to charge to 41V on a 10S battery

 

[Kinninvie]

Kinninvie just to clarify to charge the 4 MS's off the paralleled PSU's (Meanwell's) , I assume the MS's are plugged into a parallel/balance board via the watt meter and then connected to the DC/ output side of the 2nd PSU. Do you use them as they are out of the box or have you done any mods to them at all as on ES ?

If you look at the photo you will see that the terminals on one charger are wired to the same terminals on the second one.
There is then a pair of wires from that to an XT90 plug.
The negative lead passes through the wattmeter and the positive splits into 2 just out of the pic with the other wire going to power the wattmeter.
The batteries are connected together with leads from ebay.

I have not done any mods to them BUT what you do have to do is use a multimeter on each one to get the voltage EXACTLY the same.
There is a screw on the front for this.

 

[danielrlee]

I also use an Additive V2 bag.
The EM3EV bag holds one pair and is great for trail riding then if going any distance I put the V2 over and it can hold up to 6 batteries although I usually put 4 in and that leaves plenty of room for spare tubes,beer etc.
http://www.additive-bikes.com/the-backpack-for-all-frames.html

Our bikes are setup similarly - I have an EM3EV frame bag and another small triangle bag sitting on top of the crossbar in the same fashion. I am looking for additional battery capacity to hold enough for a days ride from Bath to London

I love the utility of the Additive V2 bag, but not its aesthetics. It would be much nicer all in black. The huge 'bike bag' text is awful IMO.

A few questions about the V2 bag if you would be so kind:

150 EUR is quite expensive for a frame bag. Has it been worth the money?

Is it as well made as an EM3EV bag?

I'm wondering if there would be any way to alter the appearance of the bag. What material is the grey part with the text made from?

Thanks

 

[Nealh]

Delivery for the V2 is +17 euro's, you can order a B-wear /Seconds V2 for 119 euro's + 17 delivery they apparently have imperfections ( scratch's ) etc but otherwise forfil the same criteria as the full price option.