Knoxies got some new toys

Hello

Well I placed my order for my bits at HK on the 28th of May and they finally arrived today on the 23rd of June, bit of a delay with the shipping issue hopefully my next order will arrive quicker. All of the bits were in good shape, the batteries all checked out fine I got hit with a 24 pound handling charge from the UK post office, only 11 pounds duty the rest their handling charge, this is usual, next order I think I will list it as a gift and or under 20 bucks!

Going to get going on them in the next few days will report back how I get on with them, overall I am pretty pleased with my first order from them, I will let them off the Lipo shipping thing as it was out of their hands, got so many bits now just need to get them all together.

Some pictures.

Got a bit more done tonight! cut off all of the bullet connectors and fitted 30A Anderson's, a tight fit indeed! crimped them all and then checked my harness no smoke or fumes!! ha ha, all seems fine.

Plugged them in to the charger and away it went, will report back once I have had a little run on them, looking good so far!!










View attachment IMG_2442.JPG

Wow!!

Just put 2 batteries together this morning for my run to work, the difference was amazing! batteries were 50V hot off the charger running them on my BMC Raleigh bike with 26 inch wheels I hit 29 mph on the flat and it got up there like so quickly, my old lipo batteries would be sagging down to around 32V at this point quite underwhelming, these puppies only dropped to 47.7V at 35A! in normal day to day I will be running these in parallel so I will see even less sag.

The most amazing part is the notable difference in weight! I am used to 10lbs bouncing around on the rack, it didn't even feel like these batteries were even in there! at a mere 3.4lbs! I could actually easily get away with just 2 of these batteries for my commute but want to prolong the pack life by running them in parallel, limiting the charge voltage to 4.1V and only ever using 60% of the pack, should see a few cycles with that kind of treatment.

Now to get the harness finished off, there is no way I am going to be plugging those JST connectors in and out!! got me a bunch of 37 pin D plugs and sockets coming, few spare pins there as well should I need to run any more signals back.

Heres the tiny lonesome little pack in my Topeak bag sitting snuggly in a food storage container! ha ha.



Updates to come...got to say hooray for RC Lipos!

KnoxieView attachment batts.jpg

Nice one mate!
Deciding on batteries myself at the moment.

Hi Evan

Well i can highly recommend them mate, top tips are order them now if you want them any time soon, the DE warehouse hasnt had its big shipment yet and these packs do go out of stock quite quickly, always useful to order the balance lead extensions as I did as they are so cheap, also cell alarms are really cheap all those little parts dont kick the weight up too much either.

When you ship for tax reasons set the lowest limit, I didnt i kept it at 80 dollars and got a 24 pound charge, still worth it even at that, I paid 60 bucks for shipping, had it not been for the Lipo problems that they had I would have had them in @ 14 days.

These batteries are feaking awesome! coming back home through the park near me I hit a slope that used to kill my old pack, the bike flew up this short rise lifting the front wheel up in the air! scary at 25mph on a old mountain bike! these kids shouted woooooooww ha ha the old EV grin plastered all over me face again, happy days!!

The Turnigy watt meter I got is nice but I prefer the wattsup its a lot lighter and smaller, they offer the same functions apart from the Turnigy one does 130A and is back lit, still its a nice tool for the price.

Better update my signature

Go get em you know you want to!!

Knoxie

Glad you're loving them

Once you go LiPo... It's pretty much a done-deal. LiPo could burn my house down and I would just order more packs afterwards. That's when you know you're a LiPo-slut.

knoxie said:

I could actually easily get away with just 2 of these batteries for my commute..

Click to expand...

Yeppers, for cruising I normally run just 11 of those 5.0 cells. Battery weight is a non-issue! Like it sounds you are planning to do, I also have been staying between 4.1 and 3.6v, and I run the little buzzers. No problems so far.

Is 35a the max you're going to hit them with??

Ha ha loving the comments!!

Yes my rigs are all fairly conservative compared to some on here, 35A max across 2 x packs in parallel so they will both see half of that, its plenty fast enough for me because of the lack of sag this pushes all my rides up in to the +30mph territory which Is more than quick enough for me.

Yes for commuting I may stick with the 2 x packs but it would mean the other set dont do much, I think I will still parallel them as it should help overall cycle life and then I also have the extra capacity should I wish to take a detour on the way home.

I have been charging them in the house! something they dont recommend I know, going to move it all in to the garage once I get a bigger PSU my bench PSU is struggling with 7A continuous, maybe modify up a PC supply or try and get a meanwell from somewhere.

All looking good so far!

Knoxie

:lol:

I have charged and used 2 x packs so far no problems, I got the other 2 packs on the charger and started them charging, after a couple of mins I could noticeably hear the PSU hum and then go quiet as the current to pack 2 was being switched on and off, the nice thing with this charger is that you can monitor the cells whilst they are charging, i kept seeing one cell drop to 0V then back up again :? so I unplugged it and plugged in the battery medic, all seemed fine? so I set the battery medic off in to balance mode for an hour figuring it couldnt hurt?

Went back up all looked good on the medic, so plugged back in to the charger, set the current right down low to see if I could get it to bring the cell up and straight away the charger beeped and cut out on low cell count?? when I looked again cell 6 was now reading 0V when it had been Cell 1 before? very odd anyway as I moved the pack slightly the balance wire pinged off from the charger, in my messing about I must have loosened it somehow and it was hanging on by a few pins :lol: pushed it firmly back in, checked the cells on the charger all perfectly balanced started charging and away we go check check check your connections he he.

Knoxie

Great to see you shaving off the weight and enjoying low voltage sag ! :wink:

I've found alot of variation on those Battery Medic units..

Last night i'm charging 4 packs on my Chaos ( 100v, 5ah ) and port2 shuts down " Full Charge " but the medic says 4.18v per cell... so i start the charge cycle again.. 50mah later.. Beep beep beep.. " full " .. i'm like WTF .... swap the medic for anther and 4.22 - 4.21 - .. ... ... confirm with DVM and all cells are 4.20 and over..... but the medic says 4.18

PC power supplies.... yeah.. i've been pondering that.. i have access to them for free, just dont know if i can gang them up for more amps. ???

Hi Y

Yes I am trusting my charger voltages though very pleased with the Charger, I have posted a video on Youtube detailing the charger and the set-up, I also took the BMX out for a good run this morning it was great fun, I strapped the Turnigy mini cam low down and made a mix of different shots, will edit that up later and post in the Video section

Loving the non existent sag though, I know I am not pushing these cells at all but I am so impressed by how closely matched they are staying they run cool to the touch as well.

Little video here showing the charger, I have it setup so when I turn the charger on all the profiles are loaded and I can simply just press start on each channel.

[youtube]yWVcf6fkzeM[/youtube]

Could you not run one of those as a cheap 24 cell dash monitor for an EV by modifying it? Or run it AS-IS by setting it to charge at 0.1 amps on all 24 cells with a little 12v powering it. I guess it'd need to be isolated for that though, which it probably isn't.

Definitely tempted, your bike sounds awesome with it!

8S 5.8AH appears to be $99. That's cheaper per wh than I can build a pack out of dubious LiPo from ebay vendors, I think!
A pair of those in series into a 2806 with 40A controller?

What concerns me is that they don't bother with cell voltage monitoring while discharging. That's considered very important for any other Lithium based cell, and this type is supposed to be super-dangerous :S I mean I understand why not, in the electric aircraft world, it's not worth the weight. But I wouldn't be too happy to reverse a cell while driving the bike.

Anyway I think this is the way forward for me, I'll go and read the lipo thread now

Hi Evan

I have cell alarms on each pack 4 in total, I also run cellog8 cell level monitors as well just not built the interface box yet, the cell alarms should catch any pack that falls off esp as I dont go under 50% DOD anyway.

Knoxie

Since you mention those pesky balance plugs, I found em pretty funky too. Bound to get messed up if you plug and unplug em every cycle.

I have the same cheapie buzzers. They just see pack voltage, so you can attach them to the balance leads or the power leads. So you could just crimp the wires to them into the andersons on the main leads and have them permanently attached there. One less use of the balance plugs. That would cause a tiny power drain permanently attached, so I am going to get some 2 wire plug sets for mine.

Then it sounds like your use pattery won't tend to cause any inbalance, so you could just charge without balancing most of the time, and just balance them when you have time, like weekends. So that way you use the tiny plug for balancing only a few times a month.

I was going to charge outside, but then realized, Doohh, I have a fireplace. So I'm setting the lipo on the hearth, behind the spark screen. Inside the oven is another good fireproof place in the house. If you want to charge in the house on a table, or the floor, hard tilebacker boad is a good non conductive fire resistant sheet.

dogman said:

I was going to charge outside, but then realized, Doohh, I have a fireplace. So I'm setting the lipo on the hearth, behind the spark screen. Inside the oven is another good fireproof place in the house. If you want to charge in the house on a table, or the floor, hard tilebacker boad is a good non conductive fire resistant sheet.

Click to expand...

LoL you guyz really are paranoid...better safe than sorry i guess... :lol:

Nice setup Knoxie

KiM

Yeah, I'm a real puss for reading warning labels and being careful. I got that way I the day I didn't read about contact cement, blew myself up, and ran out the door with all my exposed skin covered in burning contact cement. I love to do all kinds of dangerous stuff all the time, but one set the house and myself on fire event is enough for one lifetime. Been there done that, on to the next stunt.

Chances are, all you need with todays lipo is to put something sorta non flamable under it instead of setting it on the carpet to charge.

Hi Guys

Yes I know it does pay to be a little paranoid though I will post something on another thread that is Lipo related and happened today, not to one of my new packs though you do have to be careful. I am going to make a 37 pin DIN Anderson harness so I dont have to plug them in and out all the time.

They stay well balanced although one pack did shift out a little, no problem just ran the balance cycle on that one pack, took a little longer as my charger doesn't have massive resistors inside it for balancing but...still it works

Knoxie

I made one of these to help speed up the ballancing process..

Basically bulk charge 6S until the 1st cell hits 4.20 then disconect and hook up the anderson pigtail.. set the charger to 1S and indivicually fill each cell one at a time.

i HATE those damn JST connectors.....

Hi

Nice idea Y and yes I am with you dont think that my fingernails will stand it any more! ha ha, It will be a breeze as soon as my D shells get here I will get soldering, I need to get my Cellogs and LV brake inhibit working, at the moment I am using the buzzers but they were never going to be a permanent thing as I often ride long distance with earphones in so wanted it to cut the controller directly, all my rides will be set-up so that I can plug in the power and the brake inhibit, I run them all in parallel with my bar mounted kill switches, I run them on all my bikes its a panic switch really but it does work.

Knoxie

Ypedal said:

I made one of these to help speed up the ballancing process..

Basically bulk charge 6S until the 1st cell hits 4.20 then disconect and hook up the anderson pigtail.. set the charger to 1S and indivicually fill each cell one at a time.

i HATE those damn JST connectors.....

Click to expand...

Me too!!!!!

I like the way the cellog turned out

KiM

Thank you Kim... takes the strain off those delicate JST-XH pins and wires very effectively. Ypedal's silicone application accomplishes that as well. I'm not at all fond of those JSTs either. :?

I used a double wall heat shrink construction (2 sizes) on the CellLog, so it is really stiff and stable for repeated plugging and unplugging... It works as well as I hoped it would.

Here is a pic of the first one i did and dissected back open. My current functional version used a bit more length to allow ample room for the wires to nest in there:

View attachment IMG_0999.JPG
View attachment IMG_0961.JPG

Inspired by this thread I have ordered 2 8s batteries and a charger.. fingers crossed!

Hi Evan

Hey cool!! you wont be disappointed!! I was using an old 13.8V DC PSU that is supposed to be good for 8A continuous, in the heat we have been having lately its really been struggling and has kept powering down on over-temp, this has meant that I have had to limit each pack to just 1AH for charging, not ideal :?

I have looked in to using an old PC power supply and the pros and cons of doing that, finding one that was suitable was going to cost me nearly 50 pounds and then from my long experience with PC supplies they dont often last that long anyway :? I have gone through at least 3 on my main PC in 4 years.

So with this in mind I decided to jump in and go get a decent supply, its a useful tool as I am also a Radio Ham and this PSU is man enough to power my HF radio at full power so its got a double purpose. 8)

The local Maplin was out of stock so I contacted Moonraker over in Woburn Sands, they do a range of supplies of different sizes and types, I picked this one up for 100 pounds although they do one for 75 which is the same spec just no bells and whistles, it was a nice day and not too far for me to drive so I popped over and picked one up.

Its a nice unit I must say, its small and very well made I will put it through its paces later and see how it holds up, I never really need to charge each pack at more than 3A in reality (total 12A) however its nice to have the power if needed if I am in a hurry.

The rest of my bits came today the 37 Pin D shells and the other parts so I can get on and get rid of those pesky JST connections, here are a few shots of the supply.

If you are in the UK then I can recommend the services of Moonraker they are a radio dealer but do stock other stuff as well, nice bunch and a nice little shop as well.

Here is their website http://www.moonraker.eu/

Piccies