Hobby king multi star on offer

[Kinninvie]

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

I think its worth the money as it allows me to carry enough battery for 150 miles (if I fill the EM3EV bag as well that would be 200!).
The grey part is thick vinyl type flexible plastic and easily painted over with plastic paint.
It is well made and despite several offroad excursions over the past year its stood up perfectly.
It even has 2 bottle holder brackets to fit on the front if you require them.
I particularly like the flat top with elastic cord as its the perfect place to mount my wattmeter.
It takes less than a minute to put on or take off as well with only 3 buckles to unclip.

I often fill it with 4 batteries,a spare tube,cable lock,alarm,small bottle of pop and still have room to put a rain jacket in.

 

[awol]

Kinninvie being a regular lipo user will probably be able to offer me advice on this one - my lipos's are in storage mode for month's with a monthly topup and generally all cells have not changed except I have 1 cell which drops to around 3.73 ish at each topup. It is the first pack I bought a year or so ago to practise and learn with. Is it a sign it is weak and low on capacity or will regular use sort it to match the other cells ?

 

[Kinninvie]

Kinninvie being a regular lipo user will probably be able to offer me advice on this one - my lipos's are in storage mode for month's with a monthly topup and generally all cells have not changed except I have 1 cell which drops to around 3.73 ish at each topup. It is the first pack I bought a year or so ago to practise and learn with. Is it a sign it is weak and low on capacity or will regular use sort it to match the other cells ?

If they are charged to 3.8 and its the only one to drop then it is a weak cell but personally I would still use it but put a cell alarm on that battery set to 3.6V so it does not get too low and cause problems.
http://www.ebay.co.uk/itm/2pcs-RC-LIPO-Battery-Low-Voltage-Tester-1-8S-Buzzer-Alarm-Checker-LED-Indicator-/272048190101?hash=item3f5755f295
Of course ,if you can afford to, it would be better to replace it with a new one .

 

[Nealh]

So far so good with my lipo's I got, only been out twice as I'm quite busy with other things but checked packs to day and they are all sitting at 3.84/5v which I store charged them to. Got carried away after selling some gear on Fleabay and some Prem Bond prizes and got extra packs this time some 6.6ah's on offer.
My V2 arrived yesterday, the B - wear (2nd's') had a very slight scuff mark which is barely noticeable otherwise it is brand new, I took a pic so will upload it sometime. Fitted it today and have been arranging batt's to fit, I have reconfigured the 3 x10.4 ah packs now and will use them as 2 x 15.6ah packs plus now I have also got 1 x 13.2ah pack. For now I will continue balance charging until I'm happy with there stability then will look into the possibilities of bulk charging them and see if I'm able to serial them as 12s for charging to speed things up.

 

[Nealh]

Back to the V2 as promised a pic of the slight scuff mark which made this a 2nd's product.



Internal shot of V2.

 

[awol]

Internal shot of V2.

First test, make sure you can carry lots of botles of wine - Pass
You can always put the batteries in a backpack afterall.
Sorry couldn't resist.

 

[Kinninvie]

Back to the V2 as promised a pic of the slight scuff mark which made this a 2nd's product.

View attachment 13250

Internal shot of V2.
View attachment 13251

Mine got a bigger,deeper mark than that the first time I used it when it slipped as I put it away in tne garage.

 

[anotherkiwi]

OK I have been trying to find a "Dummies way" to get into these battery packs with the least complications.

How about:

2 x MultiStar LiHV High Capacity 6S 16000mAh Multi-Rotor Lipo Pack in series for a 45.6 V 16 Ah pack

How does the charger see the two packs in series balance wise?
What is the best solution (which charger) for charging these two packs?
Will I have to charge to 44 V or less to preserve the 36 V 09 bottle battery controller? (I think the controller components support up to 50 V)

Yes it is costly at 302€ + charger but I can't find a 16 Ah bottle battery at that price. The advantage is that I will not have a rats nest of wires to look after/understand. I don't mind charging each battery individually.

Cheers

 

[anotherkiwi]

Having written all that and thought about it I have answered my own questions!

Two chargers and split the batteries for charging is no problem. 39€ per charger, 78 € in all.

Charge each battery to 20.9 V = 41.8 V when in series which is no different from any 36 V battery. 2 x 16 Ah batteries 220 €.

A grand total of 298 € for a 16 Ah battery pack which requires supervision, I think I can handle that...

 

[derf]

Having written all that and thought about it I have answered my own questions!

Two chargers and split the batteries for charging is no problem. 39€ per charger, 78 € in all.

Charge each battery to 20.9 V = 41.8 V when in series which is no different from any 36 V battery. 2 x 16 Ah batteries 220 €.

A grand total of 298 € for a 16 Ah battery pack which requires supervision, I think I can handle that...

not trying to be clever, but I don't think 6S at 20.9V will give its full capacity ()i.e. 16Ah), also it may be flirting with damaging low voltage. having lived with hobbyking lipos ive been converted back to eclipse bottle batteries - it's the supervision, it's the risk of waking up to a house on fire (or trekking it around safe places outside)that doesn't feel worth it

 

[awol]

Two chargers and split the batteries for charging is no problem. 39€ per charger, 78 € in all.

You only need one charger as you would seperate them from series and charge both blocks in parallel so you would be charging a 5s 32aH battery. My charger of choice would be a BC168 recommended to me by d8veh which is easiest to use and also comes with a balance board.

edit: Oh just noticed you mentioned the new LiHV batteries which charge to higher volts,you will need a Lihv specific charger for those which hobbyking also sell. You still only need one though with a balance board to parallel charge them together

 

[anotherkiwi]

not trying to be clever, but I don't think 6S at 20.9V will give its full capacity ()i.e. 16Ah), also it may be flirting with damaging low voltage. having lived with hobbyking lipos ive been converted back to eclipse bottle batteries - it's the supervision, it's the risk of waking up to a house on fire (or trekking it around safe places outside)that doesn't feel worth it

If I understand one should only take them down to 3.1 V / cell which for the pack in parallel is 37.2 V. If the controller can handle 44 V peak charge that is fine with me!

I would not be charging unsupervised and not inside. I also have an alternative stocking place well out of harms way.

 

[derf]

If I understand one should only take them down to 3.1 V / cell which for the pack in parallel is 37.2 V. If the controller can handle 44 V peak charge that is fine with me!

I would not be charging unsupervised and not inside. I also have an alternative stocking place well out of harms way.

yes I run 12S (44V) with a s12sh (from BMS battery) with a BPM 340RPM in a 20 (406) wheel and it tops out at a nice relaxed 19 to 20 mph. One advantage is controllers are cheap and one cant exactly over-discharge LiHV

 

[derf]

yes I run 12S (44V) with a s12sh (from BMS battery) with a BPM 340RPM in a 20 (406) wheel and it tops out at a nice relaxed 19 to 20 mph. One advantage is controllers are cheap and one cant exactly over-discharge LiHV

I mean ito current - it being something like 20S - not voltage - I tend to avoid going anywhere near 3.1V/cell because I suspect it may reduce cycles.

 

[anotherkiwi]

Shouldn't that be 20C? OK lets play safe and go to 3.2 V

 

[anotherkiwi]

edit: Oh just noticed you mentioned the new LiHV batteries which charge to higher volts,you will need a Lihv specific charger for those which hobbyking also sell. You still only need one though with a balance board to parallel charge them together

My logic is to halve charging time and have a spare charger I can eventually chuck in the bag to take with me.

OK just read about parallel charging I understand now.

 

[KirstinS]

If I understand one should only take them down to 3.1 V / cell which for the pack in parallel is 37.2 V. If the controller can handle 44 V peak charge that is fine with me!

I would not be charging unsupervised and not inside. I also have an alternative stocking place well out of harms way.

I charge indoors as I have too

But I take the following precautions

1. In a open too metal box on a concrete base

2. The box has a smoke alarm 4 ft above it

3. There is a suitable fire extinguisher within 8 feet (not too close or far)

4. The packs are protected by foam and tupperware casing from puncture

Always worth reiterating !

 

[anotherkiwi]

The packs are 10 C which is about 100 Amps constant discharge. What are the consequences of pulling up to 18 A peak:

- little to no sagging?
- less heat (I am pretty sure about this)
- longer pack life?

 

[danielrlee]

The packs are 10 C which is about 100 Amps constant discharge. What are the consequences of pulling up to 18 A peak:

- little to no sagging?
- less heat (I am pretty sure about this)
- longer pack life?

Hobbyking are hugely optimistic regarding the power density of their lipo packs. You should derate the C rating by a factor of four to ensure a healthy battery life, low levels of heat and acceptable voltage sag.

I'd also steer clear of the 'HV' variant of the Multistar packs. They're just a marketing ploy to get you to buy new chargers if you're already invested. The regular multistar packs have been proven to a degree over the last couple of years, are quite a bit cheaper and are perfect for ebike use. They even come in 20Ah 6S packs!

 

[Nealh]

AK the folks over on the Sphere are saying that the C rates claimed by HK are ambitious, the Sphere guys reckon C rates are about 1/4 of the claimed rate. Not sure about LIHV but std lipo discharging to 3.1/3.2v is close to the cliff where they fall away very quickly, I currently set my alarms to 3.5v under load which settles down to 3.64 - 3.74 resting voltage and they appear to be staying balanced with no pack cells differing more then 0.016 volts.