Battery packs

[Andy1865]

Hi, does anybody know any makers of battery makers in the U.K. i am wanting a 24v 6ah battery for lights.
Thanks.

 

[scott gaza]

https://ebikebatteries.co.uk/ are the best but 6ah for lights? bit over kill is it not

 

[Andy1865]

https://ebikebatteries.co.uk/ are the best but 6ah for lights? bit over kill is it not

What would you recommend for 2×12v led lights then please?

 

[scott gaza]

Use them parallel and you only need the one 12v battery for them both and you would only need a small battery for led lights not 6ah I use usb recargable ones myself very bright and light weight
a 24v 6ah pack would weigh in at over 700-1050g depending on the cells used and last 150hrs at 1w

 

[Andy1865]

Use them in parrallel and you only need the one 12v battery for them both and you would only need a small battery for led lights not 6ah I use usb recargable ones myself very bright and light weight

So in a nutshell whats your best advive for the 2×12v leds and how many ah please?
Thanks

 

[scott gaza]

I would stay to 2-3 ah then your at about 150g and stil plenty of life for lights PS: What lights have you got? i use https://www.amazon.co.uk/Lezyne-Micro-Drive-500-XL-Silver/dp/B073R1RLN6

 

[Andy1865]

This is the led × 2 i have got, 9 chip to each light. When you say in parell do you mean at the side of each other.
Any chance of drawing a quick sketch and sending it to me please Scott?

 

[WheezyRider]

Andy, the important thing is the wattage of the lights and hence how much current they need. They are 12V, but how much current do they draw?

 

[Andy1865]

Andy, the important thing is the wattage of the lights and hence how much current they need. They are 12V, but how much current do they draw?

All i know about them is they are 9-85v and 15watts each.

 

[Andy1865]

All i know about them is they are 9-85v and 15watts each.

I have two single ones not the double one

 

[WheezyRider]

I have two single ones not the double one

Ok, if you are going to use 12V and they are happy being run at that voltage, then you are looking at 30/12 = 2.5 Amps.

So if you want it to run for a couple of hours, you need a minimum of 5Ah, but then probably more as battery ratings are often exaggerated and they assume a low current draw rate for their size.

I think it has been said already, can you remind me why you don't want to run this from your main e-bike battery pack?

 

[Andy1865]

Ok, if you are going to use 12V and they are happy being run at that voltage, then you are looking at 30/12 = 2.5 Amps.

So if you want it to run for a couple of hours, you need a minimum of 5Ah, but then probably more as battery ratings are often exaggerated and they assume a low current draw rate for their size.

I think it has been said already, can you remind me why you don't want to run this from your main e-bike battery pack?

Simple reason because the red and black wires are hidding inside the black battery box which holds the batteries and the controller and i do not have the tool to get into the box, thats why i am if possible going for a standalone battery now.
Thanks.

 

[WheezyRider]

Simple reason because the red and black wires are hidding inside the black battery box which holds the batteries and the controller and i do not have the tool to get into the box, thats why i am if possible going for a standalone battery now.
Thanks.

Ah, I see. If it were me, I would have had that lot in pieces by now and had the soldering iron out!

Maybe your best bet is to try one of those 12V car starter/charger packs. They are usually in the 10Ah region I think and not too expensive these days.

I am in the process of putting together some scrap LiFePO cells together to make a 12V pack for my main bike. I have a really good bright front LED lamp I'd like to use, but it is 12V max and won't run from my 14 cell main battery pack.

There is also the advantage of having a separate power setup, in that if your e-bike battery dies for whatever reason, eg you blow your main power fuse, you still have lights and can pedal home.

 

[Andy1865]

Ah, I see. If it were me, I would have had that lot in pieces by now and had the soldering iron out!

Maybe your best bet is to try one of those 12V car starter/charger packs. They are usually in the 10Ah region I think and not too expensive these days.

I am in the process of putting together some scrap LiFePO cells together to make a 12V pack for my main bike. I have a really good bright front LED lamp I'd like to use, but it is 12V max and won't run from my 14 cell main battery pack.

There is also the advantage of having a separate power setup, in that if your e-bike battery dies for whatever reason, eg you blow your main power fuse, you still have lights and can pedal home.

Any chance of sending me a link to what you mean please and do you make battery packs for other people??

 

[WheezyRider]

Any chance of sending me a link to what you mean please and do you make battery packs for other people??

I mean something like this:



Probably crap for trying to start a car with, but fine for powering 12V lights and not too expensive. You will see all kinds of ridiculous claims for Ah for these things, this particular one doesn't seem too daft.

I don't make packs for other people, but I'm happy to advise people who want to try.

 

[Nealh]

Most lithium booster power packs use a Polymer pouch (reason why they are thin/flat) even so 20,000mah still may be pushing the boundaries some what in the truth department.

This one below is similar but they are stating the mah capacity at a more realistic rating.
Peak amps are 300a.

Car Battery Jump Starter Booster Portable Power Bank 6000mAh 12V 2A 5V Charger | eBay

Find many great new & used options and get the best deals for Car Battery Jump Starter Booster Portable Power Bank 6000mAh 12V 2A 5V Charger at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

I have not tried them but most one would think will turn over a diesel car or maybe a larger suv. The only issue is the mah/cacity rating and claimed discharge current, though for lights only this isn't an issue.
My 12/3s 4500mah Li-po high rate soft pack which I use for my spot welder is rated at something ridiculous like 1300w peak and easily starts a diesel with a drained battery.

 

[Nealh]

Agree with Wheezy making packs for your self is one thing but to do so for others is leaving one self wide open.

For a 12v 6ah small light power source one only needs six times 18650 cells, an ideal cell might be the LG M36 or the Samsung 35E. It depends on how many hours riding you want with lights on.

 

[WheezyRider]

Most lithium booster power packs use a Polymer pouch (reason why they are thin/flat) even so 20,000mah still may be pushing the boundaries some what in the truth department.

This one below is similar but they are stating the mah capacity at a more realistic rating.
Peak amps are 300a.

Car Battery Jump Starter Booster Portable Power Bank 6000mAh 12V 2A 5V Charger | eBay

Find many great new & used options and get the best deals for Car Battery Jump Starter Booster Portable Power Bank 6000mAh 12V 2A 5V Charger at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

I have not tried them but most one would think will turn over a diesel car or maybe a larger suv. The only issue is the mah/cacity rating and claimed discharge current, though for lights only this isn't an issue.
My 12/3s 4500mah Li-po high rate soft pack which I use for my spot welder is rated at something ridiculous like 1300w peak and easily starts a diesel with a drained battery.

Yes 20Ah is probably pushing it, more realistically about ~10 at best, but it should be enough for some lights. I have seen claims of 60 to 80Ah on some of these products, which is just plain ridiculous.

I think probably the worst part of putting together your own pack is cell welding. This application for lights is not so bad as an ebike battery as far fewer cells are involved and current is quite low. You could take the LiPo route which usually come with solder tabs, or you could buy 18650 cells with pre-welded solder tags. However, if you're a bit worried about DIY, as I posted earlier, you can get these cheap ready made 12V capable packs for car starting.

You may even find that your 8V to 84V will run from a 5V supply as there will be a buck/boost convertor in the LED unit itself. I am currently using bike lights that originally came with an 8.4V battery pack from a normal 5V 10Ah power bank, drawing about 2 Amps. However, you'd have to find one which has high current output capability as 30W would mean at least 6 Amps. So you might have to have two power banks, one for each lamp.

 

[Andy1865]

Yes 20Ah is probably pushing it, more realistically about ~10 at best, but it should be enough for some lights. I have seen claims of 60 to 80Ah on some of these products, which is just plain ridiculous.

I think probably the worst part of putting together your own pack is cell welding. This application for lights is not so bad as an ebike battery as far fewer cells are involved and current is quite low. You could take the LiPo route which usually come with solder tabs, or you could buy 18650 cells with pre-welded solder tags. However, if you're a bit worried about DIY, as I posted earlier, you can get these cheap ready made 12V capable packs for car starting.

You may even find that your 8V to 84V will run from a 5V supply as there will be a buck/boost convertor in the LED unit itself. I am currently using bike lights that originally came with an 8.4V battery pack from a normal 5V 10Ah power bank, drawing about 2 Amps. However, you'd have to find one which has high current output capability as 30W would mean at least 6 Amps. So you might have to have two power banks, one for each lamp.

So if i add this single led to this charger it would work?. Would it go bang or just short out?. I know it sounds like a daft question but just thought id ask. Thanks

 

[WheezyRider]

So if i add this single led to this charger it would work?. Would it go bang or just short out?. I know it sounds like a daft question but just thought id ask. Thanks

Use the 12V output from that and you should be able to wire the LEDs in parallel and run them both from that pack. But for testing, I would start with just one lamp.

It would be sensible to put an inline fuse with the 12V output of say approx 6 amps or so, as the output is designed to be able to supply up to 100A, so for safety it's a good idea to add a fuse.