That's what I thought until I switched from RC chargers to a bulk charger, then like anything worth doing, wondered why I hadn't done so sooner..

What's this bulk charger?

A bulk charger outputs full pack voltage, negating the need to rearrange packs every time you want to charge. They should be used together with a BMS to pretty much 'foolproof' the charge process, but can be used without one if you know what you're doing.

A bulk charger outputs full pack voltage, negating the need to rearrange packs every time you want to charge.

Thanks danielrlee, This sound a good idea I would be interested in doing but so I don't take this thread off topic I will start a new post for help on this soon.

That's what I thought until I switched from RC chargers to a bulk charger, then like anything worth doing, wondered why I hadn't done so sooner.

 

Just something to consider before spending any more money on charging equipment.

 

So far I haven't spent a lot on chargeurs, about 30€. I don't need to charge more than twice a week. I will pull the trigger on a 300W r/c charger and a 450W PC power supply for a grand total of 90€. If I am pleased I'll get another 300W charger and sell the 80W one for 20€ with power supply which I got free.

My Graphene batteries arrived today. Slightly bulkier than Multistar. I will post a photo of the packaging tomorrow - luxury! I thought I had ordered gold bars by mistake! I paid the same price as full priced Multistar for each. Perfectly balanced at storage voltage according to battery medic.

 

I also now have a couple of alarms that work at 3.65V! Road test Monday.

My Graphene batteries arrived today. Slightly bulkier than Multistar. I will post a photo of the packaging tomorrow - luxury! I thought I had ordered gold bars by mistake! I paid the same price as full priced Multistar for each. Perfectly balanced at storage voltage according to battery medic.

 

I also now have a couple of alarms that work at 3.65V! Road test Monday.

 

Would be interested by results. Where is it discounted?

On sale in the EU store. Swank cardboard box with magnetic latches (!) padding and "felt" bag which is so black you can' get it to show in a photo

 

Why don't they just put it in a cardboard box like mutlistar and knock some more off the price? These are the batteries they like to sell to professional drone pilots apparently. Nicely balanced out of the box, is it worth the premium? Difference with the Multistar other than slightly more bulk is 15C discharge but if was drawing 150 Amps I think I would be in real trouble, maybe you will be cwah

 

 

I went for a quick ride yesterday and... well you have these wrong expectations that because you now have 20 Ah nominative the bike will go twice as fast. In fact it rides just the same let's hope it goes twice as far

 

Battery left at storage voltage of 38.4 V, peak Amps 15.12, peak Watts 576.5, minimum voltage 37.66 = 0.6 V sag up a >12% ramp.

 

Monday's planned ride is my second choice because the temperature is going up and will probably be around 38°C again... Up and down bits, trail along river on old railway line then a pass with some 12% bits for desert.

 

On sale in the EU store. Swank cardboard box with magnetic latches (!) padding and "felt" bag which is so black you can' get it to show in a photo

 

Why don't they just put it in a cardboard box like mutlistar and knock some more off the price? These are the batteries they like to sell to professional drone pilots apparently. Nicely balanced out of the box, is it worth the premium? Difference with the Multistar other than slightly more bulk is 15C discharge but if was drawing 150 Amps I think I would be in real trouble, maybe you will be cwah

 

[ATTACH=full]15427[/ATTACH]

 

I went for a quick ride yesterday and... well you have these wrong expectations that because you now have 20 Ah nominative the bike will go twice as fast. In fact it rides just the same let's hope it goes twice as far

 

Battery left at storage voltage of 38.4 V, peak Amps 15.12, peak Watts 576.5, minimum voltage 37.66 = 0.6 V sag up a >12% ramp.

 

Monday's planned ride is my second choice because the temperature is going up and will probably be around 38°C again... Up and down bits, trail along river on old railway line then a pass with some 12% bits for desert.

 

[ATTACH=full]15428[/ATTACH]

 

500W for 20AH battery?? You are underusing them! Lol

 

There must be no sag at all... maybe 0.1v on full power?

Would be interested by results. Where is it discounted?

Hobby king

For the the last 2 or 3 months the only 6S Multistar in stock in the EU is the 800 mAh...

 

The 4S 5200 mAh is at €18.89 = £15.97

 

If I had to do it all over again from the beginning the 6.6 Ah 4S packs in 2P3S for a 44.4 V - 10.5 Ah (usable) would be in first place because of the form factor, the 6S packs are too bulky. And because it would be easy to charge all at the same time at 1C with a couple of 300 W chargers and a parallel charging board.

 

All the HK chargers that are of interest are on back order so that makes choosing an iCharger bought locally a very easy decision... After looking around PC power supplies are the best solution for the € even if bought new: 20€ for 12V x 26 A 300W en sorti!

 

Sorry ! I meant to say in UK warehouse !

I only have 4 packs: 2x4S and 2x6S 10000 mAh if I had lots of say 5.2 Ah packs yes it would be an option. I have all the time in the world to charge. I spend way to much time on the internet so being there when the batteries charge isn't a real problem it is only about an hour and a half to bring all of them up from storage to 41.5V. I can read and write lots of things in that time.

 

I have exactly the same but my 2 x 4s get used daily and my 6s very rarely.

 

I've been waiting for a 4s deal to replace my ageing pair.

 

So it's good for me !

500W for 20AH battery?? You are underusing them! Lol

 

There must be no sag at all... maybe 0.1v on full power?

 

about .6 V sag. Today's stats:

 

48 km in 1:48 (26.6 km/h average)

Start voltage 41 V, end voltage 38.09 V

615.7 Watts peak (I like!)

15.14 Amps peak

325.9 Wh

8.364 Ah

 

So I used about half the battery in a 48 km ride that included a ramp at 15%. The GSM couldn't handle that with the 46:28 gearing and I don't blame it it is tough enough to walk up. This looks very much like the 100 km battery I have been dreaming of.

 

Along the river on gravel which brought back memories of my childhood and gravel rash... Did I mention I wanted a suspension seat post? Need a suspension seat post! Pit stop for fuel then the 6 km climb, a 416 m gain and mostly in 2nd gear with a couple of hairpin bends in first. The motor got hot for the first time since I've had it, it was about 36°C when I left home at 6 p.m. in the mountains between 22°C and 28°C.

 

Besides the gearing (still waiting on my 12-32 cassette) I am very pleased. Not only the new battery but also the motor and bike got a good shakedown and nothing fell off.

On sale in the EU store. Swank cardboard box with magnetic latches (!) padding and "felt" bag which is so black you can' get it to show in a photo

 

Are you talking about these cells?

http://www.hobbyking.com/hobbyking/store/__89637__Turnigy_Graphene_Professional_10000mAh_4S_15C_LiPo_Pack_w_5_5mm_Bullet_Connector_EU_Warehouse_.html

 

So at £45.59 for a 10AH 4s pack, there is 148wh. So 148/45.59 = 3.246wh/gbp.

 

A 1000wh battery would cost £308 with these pack.

 

 

If compare with Nkon:

https://eu.nkon.nl/rechargeable/18650-size/panasonic-ncr18650pf-3-7v-2900mah.html

You can get a cell from £2.6(3.05e) to £2.1(2.45e) per cell, for a 2.9ah cell we have 10.44wh. So from 4.015wh/gbp to 4.981wh/gbp.

 

A 1000wh battery would cost from £200 to £249

 

 

Unless I need high power, I would stick to NCR18650 that are 30% cheaper

Yes I know cwah you already said that in another thread. I have a 20 Ah 37 V pack that cost me 250€ (with wires and lipo alarms). If I wanted a 17 Ah 36 V 18650 battery that had 0.6 V sag (yes it is important where I live) and no spot welder what would it would cost me?

 

I could have bought a second 10.4 Ah bottle battery and paralleled it with the one I have now, 299€. Would the BMS like that? Would it sag? In any case it would be a 598€ 20.8 Ah battery if it worked so twice the price of what I have now.

Yes I know cwah you already said that in another thread. I have a 20 Ah 37 V pack that cost me 250€ (with wires and lipo alarms). If I wanted a 17 Ah 36 V 18650 battery that had 0.6 V sag (yes it is important where I live) and no spot welder what would it would cost me?

 

I could have bought a second 10.4 Ah bottle battery and paralleled it with the one I have now, 299€. Would the BMS like that? Would it sag? In any case it would be a 598€ 20.8 Ah battery if it worked so twice the price of what I have now.

 

To avoid sag issue you can just increase from 10s to 11s or 12s, especially if u only use lipo alarm and no bms.

 

But spot welder is necessary

Heads up!

 

The Turnigy Graphene Professional 5200mAh 4S 15C LiPoly Pack w/ XT60 are being heavily discounted at the moment - 28.94 € where I live. 6 in 2P3S gives you a 44.4 V 10.4 Ah nominative battery weighing 2850 grams at 174€ + postage.

 

I only have good things to say about the Graphene packs that I have, they charge faster and are balanced to within 0.01 V

More Graphene news: 5S packs now available, but they are VERY expensive. I can finally make a 15 Ah battery that fits in my frame along with the controller in the same custom battery box using 5000 mAh 5S packs. Graphene gives a 90% capacity in real world use compared to 80% with Multistar (I have gotten 87% from Multistar but really pushing it - down to 34.5 V...), so a 13.5 Ah 37 V battery - attaining the mythical 500 Whs!

 

Therein lies the dilema: buy a new frame that accepts a HL battery with internal controller or roll my own battery box. Option one is more expensive, option two is more "complicated" to live with...

 

3P2S packs at 45C nominative should pack quite a punch on the hills especially as I will only be drawing 1C. Sag should be reduced to the absolute minimum.

 

I will wait for them to go on sale later in the year and grab me some.

I went for the 10 C batteries, but 16ah so 160a rated, not much sag with that setup pulling 16 amps

Ok so SW you could flatten my battery quickly.

i want 200hp 200000kw for my mobility scooter when i retire ill get the lap record round tesco on that

Can you put a 12aH 6s in series with a 10aH 4s ?

Can you put a 12aH 6s in series with a 10aH 4s ?

You can

 

But....it isn't a great idea unless you plan to use a small amount of capacity before recharging

 

You'll quickly end up killing the lower 10ah pack otherwise

 

I have a 5200mah 4s and a 6600 mah 6s

 

I do series them for a stealth,local,runaround, occasional pack. But it's very apparent even with low usage how the state of charge differs very quickly . Apparent on recharging that is

 

My experience and opinion of Lipo anyway

You can

But....it isn't a great idea unless you plan to use a small amount of capacity before recharging

You'll quickly end up killing the lower 10ah pack otherwise

I have a 5200mah 4s and a 6600 mah 6s

I do series them for a stealth,local,runaround, occasional pack. But it's very apparent even with low usage how the state of charge differs very quickly . Apparent on recharging that is

Those 6s 12aH packs are on offer under £49, so a 44v 12aH battery for under £98 + p&p

so I'll probably go for a 2 of them instead.

Edited January 20, 20179 yr by awol

Has anyone recently ordered any 16000mAh Multistar bricks (4S or 6S) from the HobbyKing UK warehouse? They're only currently available from the Aus or Global warehouses and I was wondering if they've recently become out of stock, or whether they've been on backorder for a while.

 

Probably a long shot, but I don't suppose anybody has a new/nearly new 4S 16000mAh Multistar pack that they're looking to sell?...

Edited February 20, 20179 yr by danielrlee