Turnigy Graphene.

[Nealh]

I just received some 8ah Turnigy Graphenes from Hobbyking and they come very well packed, the 8's were on offer so decided to get some to try them out and another 16ah of riding options.
Noticeably they are/seem quite heavy a 10s battery being 4lbs total and handily come with the XT60
connector.
The battery comes in a soft pull string pouch nicely encased in a decent flip lid box lined with grey foam, no use for the packaging but seems to good to throw away.



Magnetic closure lid.

 

[Topdonkey]

Very nice, it might be time soon for me to get a new set of batteries as my tunigy multistars seems to be dying slowly 1 cell at a time, I've lost 2 cells in the last month that have dropped to 0v suddenly although the overall capacity of the pack remains pretty much the same as it was 2 years ago when new.

But i'm just curious as to what benefit the graphene lipos have over the non graphene ones ?, I thought it was just higher discharge potential ? which isnt needed on an ebike or is there something else ?

 

[Woosh]

sorry to go off topic.
what do you people think of small Lithion ion battery cell packs like this one:

Capacity: 36V 10.2AH
Panasonic 18650 10S3P
Maximum continuous discharge 15A
Weight: 1.7kgs
Dimensions: 60mm x 115mm x 140mm
30A Anderson connectors for output, jack socket for charger.
Supplied with Li-ion 2A intelligent charger.
No bag.

 

[craiggor]

sorry to go off topic.
what do you people think of small Lithion ion battery cell packs like this one:

Capacity: 36V 10.2AH
Panasonic 18650 10S3P
Maximum continuous discharge 15A
Weight: 1.7kgs
Dimensions: 60mm x 115mm x 140mm
30A Anderson connectors for output, jack socket for charger.
Supplied with Li-ion 2A intelligent charger.
No bag.

Are you selling them ?

 

[anotherkiwi]

Very nice, it might be time soon for me to get a new set of batteries as my tunigy multistars seems to be dying slowly 1 cell at a time, I've lost 2 cells in the last month that have dropped to 0v suddenly although the overall capacity of the pack remains pretty much the same as it was 2 years ago when new.

But i'm just curious as to what benefit the graphene lipos have over the non graphene ones ?, I thought it was just higher discharge potential ? which isnt needed on an ebike or is there something else ?

They charge faster, MUCH faster. They are balanced beyond belief and stay balanced. They don't get warm (in normal use). I could go on... They are slightly heavier and larger. They are given for +600 recharge cycles (field tested by the drone boys, if they can be trusted) if you use them between 4.15 and 3.65 V.

The same article I read on the RC site had people getting at least 95% of the mAh printed on the label - that is good for e-bike use!

And if you live at the foot of mountains and need 17 Ah constant, they provide without sag, I have seen 0.6 V sag maximum but my battery is a mix of Graphene and Multistar. In normal use, assistance level 3 and the correct gear they sag by about 0.1 V on the hills.

 

[anotherkiwi]

sorry to go off topic.
what do you people think of small Lithion ion battery cell packs like this one:

Capacity: 36V 10.2AH
Panasonic 18650 10S3P
Maximum continuous discharge 15A
Weight: 1.7kgs
Dimensions: 60mm x 115mm x 140mm
30A Anderson connectors for output, jack socket for charger.
Supplied with Li-ion 2A intelligent charger.
No bag.

If you can price them the same as 12 Ah of LiPo yes I would buy 2 to use in parallel so that I could be sure of getting 17 A continuous discharge and 18-20 Ah.

 

[Woosh]

No, they are not as cheap as lipo. They are made with NCR18650B, 3,400mAH x 3 = 10.2AH and BMS - just uncased so you can build your own case, maximizing the benefit of light weight (1.7kgs).
You only save about £20, the cost of the case.
The pack is small enough to go inside your coat pocket.

 

[Nealh]

Graphene as AK has said charges faster, the spec says up to 5c.

 

[Woosh]

Are you selling them ?

Not yet.

Graphene as AK has said charges faster, the spec says up to 5c.

You can charge them faster than 2A but that will shorten the life of the pack. At 4A, you may have only 300 cycles.

The idea is you only need to carry enough for your ride, 1 pack for 30 miles, 3 packs for 100 miles.
Keeping unsprung weight low. Andersons take seconds to swap.

 

[Topdonkey]

They charge faster, MUCH faster. They are balanced beyond belief and stay balanced. They don't get warm (in normal use). I could go on... They are slightly heavier and larger. They are given for +600 recharge cycles (field tested by the drone boys, if they can be trusted) if you use them between 4.15 and 3.65 V.

The same article I read on the RC site had people getting at least 95% of the mAh printed on the label - that is good for e-bike use!

And if you live at the foot of mountains and need 17 Ah constant, they provide without sag, I have seen 0.6 V sag maximum but my battery is a mix of Graphene and Multistar. In normal use, assistance level 3 and the correct gear they sag by about 0.1 V on the hills.

Ahh, so not just discharge rate improvements then, my multistars can charge at up to 2c, but i struggle to find a charger that can better a 1c charge anyway, a 14s pack of 16ah multistar batteries charging at 1s needs a 940w power supply, so to charge it at 5c would need a 4.7kw charger !!!!!!! thats more than a standard mains socket can supply, although it would charge in less than 15 minutes then which could be handy if i forgot to charge it beforehand

 

[anotherkiwi]

I charge at 1C because I have the time and the 10000 mAh 6S Graphene charges from storage voltage to full in about 38 minutes, Multistar about 43 minutes. I have a couple of 250 W chargers behind a 540 W poser supply.

 

[danielrlee]

I've just taken receipt of 9000W of power supplies:

I'm yet to do the maths, but they'll charge your graphene lipos pretty bl**dy quick!

 

[awol]

I got a couple of those 8000mah bad boys the other week when they were on sale too. It turns out 8000mah isn't enough for me though.
Can you permanently parallel different mah packs?
i.e a 6s8000mah with a 6s4000mah to make a 6s12000mah pack? I know you can do that to charge but how about discharging?

 

[D8ve]

I got a couple of those 8000mah bad boys the other week when they were on sale too. It turns out 8000mah isn't enough for me though.
Can you permanently parallel different mah packs?
i.e a 6s8000mah with a 6s4000mah to make a 6s12000mah pack? I know you can do that to charge but how about discharging?

Yes you can do that.
But split for charging on the balanced chargers

 

[Deleted member 4366]

I got a couple of those 8000mah bad boys the other week when they were on sale too. It turns out 8000mah isn't enough for me though.
Can you permanently parallel different mah packs?
i.e a 6s8000mah with a 6s4000mah to make a 6s12000mah pack? I know you can do that to charge but how about discharging?

Don't forget that you can use a balance board for easy parallel connection. Take off the back and beef up the main power tracks, then you can leave them connected when you charge and discharge. Cheaper than makin/buying a parallel lead:

http://www.ebay.co.uk/itm/6-1-Parallel-Charging-Balance-Board-for-Lipo-LiFe-Li-ion-IMAX-B6-Battery-Charger-/401001007226?hash=item5d5d85c87a:g:v~kAAOSwUKxYavpJ

 

[anotherkiwi]

I got a couple of those 8000mah bad boys the other week when they were on sale too. It turns out 8000mah isn't enough for me though.
Can you permanently parallel different mah packs?
i.e a 6s8000mah with a 6s4000mah to make a 6s12000mah pack? I know you can do that to charge but how about discharging?

IIRC that will mean a different C rate from each pack. This isn't a problem if you are drawing 15-20 Amps on an e-bike. If you are drawing full Amps in an R/C situation your max C rate will be limited to that of the smallest pack.

I am running Graphene paralleled with Multistar - both are the same mAh and C rate. Since I have been doing this the Multistar 6S has stayed better balanced. The 4S which has a weak cell now has a strong cell (not the same one) and three weaker...

 

[danielrlee]

IIRC that will mean a different C rate from each pack. This isn't a problem if you are drawing 15-20 Amps on an e-bike. If you are drawing full Amps in an R/C situation your max C rate will be limited to that of the smallest pack.

This isn't the case when paralleling packs, only when connecting in series. As long as the paralleled packs are the same voltage, there shouldn't be any issue.

 

[anotherkiwi]

Just a quick update after just over 2 years constant use.

- Today I checked the packs with my battery medic before charging (I always check after) all cells were at 3.82v. Every single one on both bricks! One cell on the 4S brick dropped to 3.81v, the battery medic has very slight current draw so I guess it took just enough mAh from the battery to bring it down to 3.819v...

- On the way home from work it was 10°C and on the steepest climb I saw 2v battery sag. This is the first time I have noticed so much but - over two years old, big drop in temperature from the 20°C of last week and at the bottom end of charge.

Global appreciation is well worth the extra cost seeing I got them on sale and the use they have had. My Multistars kicked the bucket months ago. And irony of sorts it was the 6S that went first, not the always iffy 4S...

 

[vfr400]

Do you know roughly how many equivalent full charges you got out of the Multistars and how many the Turnigys have done?

Or how many miles?

 

[anotherkiwi]

I'm not good at keeping stats... Looking back over my threads and HK bills:

The Multistars were bought on sale in March 2016 so were just about 3 1/3 years old when they started failing. The Graphene on sale in September of the same year so they are 3 years old.

In that time I have done over 7,500 km on LiPo either alone or, in the first 6 months I had the Multistar parallel with the 10.4 Ah bottle battery that came with my kit. I would say that the 6S Multistar had participated in well over 5,500 of those km - the last couple of years it was mostly used in series as a 12S with the 6S Graphene. The 4S spent at least a year at storage voltage in the cupboard during that time. Cost wise less than 0.02€/km for the Multistars.

When the bikes were an off work activity I was charging weekly or twice weekly depending on km, I would say +300 charge cycles for the Multistars. Since September of last year I commute and I charge every 3 days so 120 charge cycles a year. I get 8000 mAh from a charge of the 36v Graphene batterie, so 80% of what is on the wrapper. If I was living in a flatter place I would most likely still get 9000 mAh, that last hill means I never go below 3.8v before charging. All Multistar charges were full charges from 3.65v to 4.15v per cell.

PS: If you look on the HK site you might notice that Mutlistar is no longer there...