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Smaller, subtle 48v battery options?

Featured Replies

Hey guys, I've finished my eBike conversion but finding the battery is a bit overkill what the journeys I do.

 

I purchased the 48v 18aH battery from Insat Batteries / Jimmy and its amazing no doubt. The issue is that I have a road bike with no suspension and the battery is a bit too 'wobbly' on the frame and adding a bit too much extra weight to that area.

 

I did a 16mile ride last week and the battery display didn't drop a single bar out of the 4. My commute is only 6 miles!

 

I understand that you need a big battery so that when its depleted slightly it still has plenty of power, but I think for these smaller journeys I could do with something smaller.

 

I ideally wan't to get a bottle battery and actually fit it inside of a real water battle for the stealthy look, has anyone has luck with a smaller 48v battery for around 10 miles max and knows roughly what aH I should look for?

 

Picture of said bike, just because :)

 

IMG_8635.jpg

  • Author

Hey

I can sell you a 48V 12AH HL battery.

 

Hey Woosh, what does the HL part mean?

 

Do you happen to have any dimensions for such battery too?

HI style are more stealthy and fit lower and sleeker on the tube. On my medium size frame it looks like this

 

07d6f0977c27085872c4f55255654b81.jpg

 

For a truly stealth build in an actual water bottle you'll need to diy. Or have someone like Jimmy at bga reworking do it for you. It's trickier with 48v as you'll need more cells for the same ah pack. D8veh did a good build thread on this subject . I'll find it for you . I think he got enough cells and a bms inside which gave a 6ah pack (using 3000ah cells )

 

 

Thing is you need 13 in series not 10 to get 48v so it's a bit of a struggle . I think you need to find an oversize bottle to get it to work as 26 cells is really your minimum. Which may defeat the objective .

 

 

 

Sent from my iPhone using Tapatalk

Here it is

 

http://www.pedelecs.co.uk/forum/threads/how-to-make-a-lightweight-battery.28437/

 

 

As i thought he used 20 cells in total (2 layers of 10 cells , 10s 2p formation to get 36v ah from 3000ah cells) but you'd need 26 to get 48v . So you need a bottle that can either fit 13 per layer or is longer to take 3 layers

 

Hope that makes sense.

 

It's the downside to 48v I'm afraid , need more cells ! A single cell series of 13 cells will not give you the range you need (looking at 3.5ah max)

 

Hl are my favourite design of mainstream packs to date though. Stick some extra rivenuts into your frame so you have three (or more ) anchor points

 

My bike has been thrown down some serious trails and done 1000miles without issue in this setup.

 

Your only other option is to buy a frame /triangle bag and stick a battery in that. Looks less ebike but more like a trekking machine. And it isn't anchored in the same.way

 

Sent from my iPhone using Tapatalk

Edited by KirstinS

Or 12S 44.4v nominative (50v hot off the charger) with 24 x Sanyo 20700 cells for an 8 Ah battery with 30 Amp discharge weighing 1.51 kg without the BMS.
Or 12S 44.4v nominative (50v hot off the charger) with 24 x Sanyo 20700 cells for an 8 Ah battery with 30 Amp discharge weighing 1.51 kg without the BMS.

 

Yeah but the lvc will kick in a bit too early so the 8ah won't all be usable , I think ?

 

 

Sent from my iPhone using Tapatalk

If you use a KT LCD-3 you can set it and get down to about 3.5v per cell so yes you miss out on the last 0.2v.

 

On the other hand the Sanyo is rated for over 4100 mAh so... I was being pessimistic when I said 8 Ah :)

a side observation: batteries need to be in a UN 38.3 casing if it is on public roads.

Cell packs in a bike bag would be illegal.

a side observation: batteries need to be in a UN 38.3 casing if it is on public roads.

Cell packs in a bike bag would be illegal.

 

Im not convinced about this woosh. 38.3 is about shipping saftey. It's s not a requirement for use on a bike as far as I can see.

 

http://www.metlabs.com/battery/un-38-3-transportation-testing-required-for-lithium-battery-safety-during-shipping/

 

 

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Im not convinced about this woosh. 38.3 is about shipping saftey. It's s not a requirement for use on a bike as far as I can see.

 

http://www.metlabs.com/battery/un-38-3-transportation-testing-required-for-lithium-battery-safety-during-shipping/

 

 

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reasons:

1. the cell pack has to be shipped to you. It needs to be done in an UN 38.3 case.

2. If an accident happens on a public road involving your cell pack, how are you going to defend the case?

Its air freight regulation. Nothing to do with use at all

 

I buy a battery from jimmy in north London and collect by car. I put in a frame bag

 

In case of accident what case is there to answer , I have done nothing wrong that I can see. What law is broken ?

 

if the 38.3 relates to anything other than Air freight and , in particular , relates to use by individuals on their bikes then I'd like to see the evidince for that please

 

 

 

 

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Its air freight regulation. Nothing to do with use at all

 

I buy a battery from jimmy in north London and collect by car. I put in a frame bag

 

In case of accident what case is there to answer , I have done nothing wrong that I can see. What law is broken ?

 

if the 38.3 relates to anything other than Air freight and , in particular , relates to use by individuals on their bikes then I'd like to see the evidince for that please

 

 

 

 

Sent from my iPhone using Tapatalk

 

https://www.bike-eu.com/laws-regulations/artikel/2010/08/eu-regulations-for-e-bikes-pedelecs-part-4-battery-transportation-1018848

 

QUOTE:

 

Any Lithium-Ion battery over 100 Wh is classified as CLASS 9 – MISCELLANEOUS DANGEROUS GOODS under the dangerous good regulations for transport by road (ADR), by air (IATA & IACO) and by sea (IMDG). Lithium-Ion batteries for pedelecs are more than 100 Watt-hours. As a result, their transport has to comply with these regulations. The UN number for Lithium-Ion batteries is 3480, if contained in or packed with equipment 3481.

 

These rules do not only concern transport of batteries for instance from manufacturer to dealer, but all transport except transport for private purposes. First of all, to ship goods in the CLASS 9 category means that the battery needs to be tested in accordance with the UN Manual of tests and criteria, Part III, subsection 38.3.1.

PS: even the carton and infill should be made with 4G certified board.

UN 38.3 above implies transportation from manufacturer to supplier/seller to end user, the transportation does not apply to the end user in a private capacity.

before I buy a battery from a factory, I always ask for their UN certificates.

without UN38.3 casing, the battery is not safe if it hits the road, not safe if it is left outside in hot weather.

UN 38.3 above implies transportation from manufacturer to supplier/seller to end user, the transportation does not apply to the end user in a private capacity.

 

Exactly Nealh. Thus the initial statement by Woosh simply isn't true

 

 

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you guys should read the article I linked to, in its entirety if possible.

The author explains better than I could possibly do.

I have no interest in alarming unnecessarily anyone.

All batteries for e-bikes must be tested for puncture and overcharging without bursting into flames.

Single, custom cell packs can't be tested and therefore illegal to use.

The problem is the law does not stop people selling something illegal to use.

 

https://www.bike-eu.com/laws-regula...edelecs-part-4-battery-transportation-1018848

 

PS:

 

Here is a quote from Halfords

 

https://www.halfords.com/advice/cycling/expert-advice/e-bikes-faqs

 

  • The battery pack has to be fully approved to UN / DOT 38.3. This includes extreme charging and discharge testing, along with high temperature and physical abuse tests.

Edited by Woosh

The article is about transporting/supplying batteries on or off a bike and not their actual use by the end user.

 

 

"If any company handles, packs and labels dangerous goods, such as Lithium-Ion batteries at their own premises, a trained “Dangerous Goods Advisor” is required onsite to oversee that this is done in full compliance with the rules and to declare the goods safe to travel. If you have no member of staff which has received the above training, you must hire a specialist company to handle, pack and label the goods and to fill out a “Dangerous Goods Note”. It is compulsory for Dangerous Goods shipments to be accompanied by this document"

If you don't believe me, just google "do e-bikes batteries have to be UN38.3 certified"

 

There have been plenty of threads on here about 38.3 over the years.

 

BTW, soon I won't be allowed to repair batteries because a faulty battery cannot be moved unless to the tip. Batteries are made nowadays unrepairable by design.

 

QUOTE:

 

As of 1 May 2012, battery packs – including those intended for use in medical products – must be evaluated for full compliance to IEC 62133.

 

The International Electrotechnical Commission (IEC), a non profit standards organisation, writes international standards for all electrical, electronics and related technologies, including batteries. For lithium batteries, the key standards are IEC 62133, the IEC 60086 suite, IEC 61960 and IEC 62281 (the IEC version of UN 38.3)

...

 

“Is the Battery UN38.3 certified?”

If not it cannot be legally handled in the UK and why is someone selling an uncertified lithium battery? You’d be surprised how often we hear of unapproved batteries coming in from places like China. The problem is you can’t legally move them. The regulations around battery movement are pretty tight these days and you need to have the right certificate and the right box to transport them in. If it doesn’t have these and you want to send it in for repair, how are you going to do that?

 

UN38.3 certification has been specifically set up to cover the safe storage and shipping of lithium batteries.

 

Lithium ion electric bike batteries are safe as long as they have been built to the correct standard.

Edited by Woosh

for a long time, I wanted to make a kit for the Brompton but because the Brompton is rather 'bijoux', a custom battery is needed. I bumped into so many regulatory issues that need to be sorted before I can get product liability insurance, that project is still on the drawing board.

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