Ok thank you. Now if i could as you another question please, how do i connect an inline fuse and where do i buy the said fuse please?
Battery packs
- Thread starter Andy1865
- Start date
I've got one open here. It's an ordinary lipo with no markings. Comparing it's size with my others, I'd say its capacity is about 2.8Ah. I'm pretty sure that it's 4S, though it has a 5S balance connector with two reds, which would be about 40WH, which would drive the lights for about an hour at full power. I wouldn't recommend one of these devices. The lipo had swollen up before it was ever used, which is why it was given to me to dismantle.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.
You could use any decent lipo from Hobbyking, though you'd need a cell alarm and charger too. The lights can run at any voltage, so a 6S 4Ah would give 57Wh or about 9 minutes use at full power, but that will cost around £60 just for a cheapish battery and charger, which is a lot more than the 24v 6Ah pack that I already showed him, and it'll be more dangerous and more labour intensive re charging and monitoring.
Are you sure that 24V pack in the other thread you posted in would be ok? It looks a lot like other packs advertised on Ali Express you've said previously most probably contained recycled cells. It comes with an EU plug too which is not ideal.
Andy, you can get an inline fuse from Ebay, of all shapes, sizes and capacities...or even Halfords would have one for a couple of pounds, you could use a car 10A spade type fuse.
While I agree that LiPo cells are bad news in large current draw applications, something like this should not be a major issue as it's relatively low current. Also, not all of these devices use LiPo cells, some use 18650s.
I've got one of these starter charging things somewhere. I'll dig it out, connect it to my 18W lamp and see how long it runs for and get back to you.
While I agree that LiPo cells are bad news in large current draw applications, something like this should not be a major issue as it's relatively low current. Also, not all of these devices use LiPo cells, some use 18650s.
I've got one of these starter charging things somewhere. I'll dig it out, connect it to my 18W lamp and see how long it runs for and get back to you.
I wouldn't use one to power a bike, but should be fine for running lights at 1.25 amps.
Thank you Wheezy.
Would there be any chance of you drawing me a diagram on how to set up the car battery pack to the leds via the inline fuse and i'd like to include a bog standard on/off switch also please
Would you consider selling me your starter thing and charger, least that way i'd be positive it would work for me?
Well let's not get ahead of ourselves. I have tested it on my lamp before and it works, but not looked into how long it would run for. Let me do the test and get back to you. But even then it will probably easier and better to buy your own, the one I have is quite a few years old and has sat in my garage fro years unused.
This is something that might be worth considering as your lamps can run from 8.4 V:
The nice thing about this is that you can put your own cells in it and not have to worry about welding cells to form a battery. It looks like a 2s 3p config, so you could have high capacity 3.5 Ah 18650 cells, giving you a capacity of about 10Ah at 8.4 V It also comes with the straps needed to mount it on the bike. You would need the cells obviously, and also a charger, but a charger can be found quite cheaply for 8.4 V. Nkon is a good place to get cheap but quality cells:
LG INR18650-MJ1 3400mAh - 10A - 18650 - Li-ion - Rechargeable batteries | NKON
<p>LG INR18650 MJ1 3500mAh (10A)</p> <p><a href="/sk/k/Specification%20INR18650MJ1%2022.08.2014.pdf" target="_blank">Datasheet </a></p>
eu.nkon.nl
For a single lamp at 15W, you'd be looking at a current draw of about 2 amps or about 4 amps for two lamps in parallel. That would give up to 5 hours for a single lamp and a couple of hours for two lamps. You could always have two packs, one for each lamp. You may even have two switches so you can switch lamps independently. Looks like this battery case has an internal BMS controlling the output. Looks like max output is 9A from the spec given.
See what you think...
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There's a downside to those cases. There's no low voltage cut-off and I think there's constant drain on the cells when not in use. My one has bricked about 3 sets of cells so far because I can't be bothered to take them out when I don't use it. It's no problem for me because I have boxes full of reclaimed cells from Ebike batteries, but it could work out expensive if you buy new 3.5Ah cells at £24 for a set of 6.This is something that might be worth considering as your lamps can run from 8.4 V:
View attachment 39247
The nice thing about this is that you can put your own cells in it and not have to worry about welding cells to form a battery. It looks like a 2s 3p config, so you could have high capacity 3.5 Ah 18650 cells, giving you a capacity of about 10Ah at 8.4 V It also comes with the straps needed to mount it on the bike. You would need the cells obviously, and also a charger, but a charger can be found quite cheaply for 8.4 V. Nkon is a good place to get cheap but quality cells:
LG INR18650-MJ1 3400mAh - 10A - 18650 - Li-ion - Rechargeable batteries | NKON
<p>LG INR18650 MJ1 3500mAh (10A)</p> <p><a href="/sk/k/Specification%20INR18650MJ1%2022.08.2014.pdf" target="_blank">Datasheet </a></p>
For a single lamp at 15W, you'd be looking at a current draw of about 2 amps or about 4 amps for two lamps in parallel. That would give up to 5 hours for a single lamp and a couple of hours for two lamps. You could always have two packs, one for each lamp. You may even have two switches so you can switch lamps independently. Looks like this battery case has an internal BMS controlling the output. Looks like max output is 9A from the spec given.
View attachment 39250
See what you think...
Good points. From the spec sheet it says cut off at 5V, so a little on the low side. Doesn't say the drain in standby mode, so that would have to be checked. Quite often cheaper USB power banks are "always on" causing a bit of drain in standby, but it's not huge, on this one there seems to be an on/off button, so maybe it is more like the ones that shut down completely if there is no load until the on button is pressed again. If it is an issue, you could just take a couple of cells out when not used for a long time.
Yes you wouldn't want to put really expensive cells in it if they are going to get killed by it, but I do like the flexibility it gives you. You could use cheap cells and just have a spare set to swap in when you want.
Ok, I dug out the starter charger I bought a few years back and had a look at it for running 12V LEDs.
Here is the box and it claims 26Ah:
This is what's in the box. The charger/starter unit itself, a wall charger, a load of adaptors and some crock clips for connecting to a car battery. This model has extra functions, like being able to switch the charger output from 5V to 20V, so you can even run laptops from it:
I have never actually used it in anger to try and start a car. The one time I had a flat battery and I tried to use it, nothing happened. I later realised that the thick wire soldered to the reverse polarity protection diodes on the positive lead had become detached, hence no power was output. Oh, the joys of lead free solder...
So let's open it up and have a look. A fair bit of electronics and a battery pack of, wait for it, 3.8 Ah!! The 11.1V nominal suggests 3 cells at 3.7V. Probably LiPos in that shrinkwrap. The OCV was 12.4V from the 12V starter socket. The entire unit weighed about 400g.
So let's connect it to a 12V LED lamp. I bought this LED lamp a while ago. It's for attaching to cars to add extra driving lights. It runs at 1.5 A at 12V, so 18W. I like the housing as it has a decent heatsink to keep it cool:
I charged the starter/charger to 100% and I inserted the croc clips cable into the car starter socket on the unit. Then I connected them to the LED lamp:
I let it run for 1hr and 40 min. The charge indicator went from 100% to 35% in that time. Voltage output dropped to 11.1V and the current was just over an amp.
I expect this particular unit could power this LED for a couple of hours. This would be fine for me, most of my journeys are far less than an hour. However, I decided against using it as it is a bit bulky for what I need, with all the extra stuff on it for supporting lots of charging output options.
In summary, I think these units have some utility for running 12V ancillary equipment on e-bikes, as an "off the shelf, contained solution", but just don't believe the quoted Ah values at all! However, if you are comfortable with building your own battery pack, I think that would be the optimal solution.
If you do use one of these, I do think it is a good idea to put an inline fuse in the output for safety.
Here is the box and it claims 26Ah:
This is what's in the box. The charger/starter unit itself, a wall charger, a load of adaptors and some crock clips for connecting to a car battery. This model has extra functions, like being able to switch the charger output from 5V to 20V, so you can even run laptops from it:
I have never actually used it in anger to try and start a car. The one time I had a flat battery and I tried to use it, nothing happened. I later realised that the thick wire soldered to the reverse polarity protection diodes on the positive lead had become detached, hence no power was output. Oh, the joys of lead free solder...
So let's open it up and have a look. A fair bit of electronics and a battery pack of, wait for it, 3.8 Ah!! The 11.1V nominal suggests 3 cells at 3.7V. Probably LiPos in that shrinkwrap. The OCV was 12.4V from the 12V starter socket. The entire unit weighed about 400g.
So let's connect it to a 12V LED lamp. I bought this LED lamp a while ago. It's for attaching to cars to add extra driving lights. It runs at 1.5 A at 12V, so 18W. I like the housing as it has a decent heatsink to keep it cool:
I charged the starter/charger to 100% and I inserted the croc clips cable into the car starter socket on the unit. Then I connected them to the LED lamp:
I let it run for 1hr and 40 min. The charge indicator went from 100% to 35% in that time. Voltage output dropped to 11.1V and the current was just over an amp.
I expect this particular unit could power this LED for a couple of hours. This would be fine for me, most of my journeys are far less than an hour. However, I decided against using it as it is a bit bulky for what I need, with all the extra stuff on it for supporting lots of charging output options.
In summary, I think these units have some utility for running 12V ancillary equipment on e-bikes, as an "off the shelf, contained solution", but just don't believe the quoted Ah values at all! However, if you are comfortable with building your own battery pack, I think that would be the optimal solution.
If you do use one of these, I do think it is a good idea to put an inline fuse in the output for safety.
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Nice one Wheezy, by opening up the booster pack you have proved what we have been saying for a long time. The quoted mah capacity given is just a figment of the sellers imagination and any random figure can be printed on the packaging.
One only has to look at the top lipo cells available to know that, any thing more then 4000/5000mah is pretty much the limit for some of these small size lipo pouch's used.
One should be wary of calling them chargers as they certainly aren't, an alternate energy supply is what they are.
One only has to look at the top lipo cells available to know that, any thing more then 4000/5000mah is pretty much the limit for some of these small size lipo pouch's used.
One should be wary of calling them chargers as they certainly aren't, an alternate energy supply is what they are.
The small red box on the + cable is that not a fuse?Ok, I dug out the starter charger I bought a few years back and had a look at it for running 12V LEDs.
Here is the box and it claims 26Ah:
View attachment 39266
This is what's in the box. The charger/starter unit itself, a wall charger, a load of adaptors and some crock clips for connecting to a car battery. This model has extra functions, like being able to switch the charger output from 5V to 20V, so you can even run laptops from it:
View attachment 39267
I have never actually used it in anger to try and start a car. The one time I had a flat battery and I tried to use it, nothing happened. I later realised that the thick wire soldered to the reverse polarity protection diodes on the positive lead had become detached, hence no power was output. Oh, the joys of lead free solder...
So let's open it up and have a look. A fair bit of electronics and a battery pack of, wait for it, 3.8 Ah!! The 11.1V nominal suggests 3 cells at 3.7V. Probably LiPos in that shrinkwrap. The OCV was 12.4V from the 12V starter socket. The entire unit weighed about 400g.
View attachment 39265
So let's connect it to a 12V LED lamp. I bought this LED lamp a while ago. It's for attaching to cars to add extra driving lights. It runs at 1.5 A at 12V, so 18W. I like the housing as it has a decent heatsink to keep it cool:
View attachment 39268
View attachment 39269
I charged the starter/charger to 100% and I inserted the croc clips cable into the car starter socket on the unit. Then I connected them to the LED lamp:
View attachment 39270
I let it run for 1hr and 40 min. The charge indicator went from 100% to 35% in that time. Voltage output dropped to 11.1V and the current was just over an amp.
I expect this particular unit could power this LED for a couple of hours. This would be fine for me, most of my journeys are far less than an hour. However, I decided against using it as it is a bit bulky for what I need, with all the extra stuff on it for supporting lots of charging output options.
In summary, I think these units have some utility for running 12V ancillary equipment on e-bikes, as an "off the shelf, contained solution", but just don't believe the quoted Ah values at all! However, if you are comfortable with building your own battery pack, I think that would be the optimal solution.
If you do use one of these, I do think it is a good idea to put an inline fuse in the output for safety.
No, it is a PCB with some semiconductors on it. I'm not totally sure of all its functions. It is at least a reverse polarity protection system, but it may also limit current to say 100 A, like a battery BMS does. This is too much for low current circuits though and could cause problems if you happened to have a short (burn things out, start a fire, burn fingers etc).
These things are designed to give 200amps, so even if it were a fuse, it wouldn't be much good for lights. The answer is no, anyway.
Thanks for the info, Wheezy. That's very similar to my one, except mine has a 4S battery. Lipos, especially cheap ones, drop off much more quickly than ebike batteries. I used to use them on my ebikes in the days when that was the only way to get 30 amps. I used 12S. When they were down to 44v, I needed to be very close to home. I would say the meter is a bit optimistic, and you had maybe 10% left.
Just thought people would like to see exactly what is inside the red box on the positive power lead...
See the nice blob of leaded solder on one side (my repair) and the unleaded solder on the other?
So there are 4x MBRB2545CT 30Amp, 45V Schottky diodes for reverse polarity protection. Specs can be found here:
See the nice blob of leaded solder on one side (my repair) and the unleaded solder on the other?
So there are 4x MBRB2545CT 30Amp, 45V Schottky diodes for reverse polarity protection. Specs can be found here:
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