Charging Electric Bike Batteries
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colinm
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We have a cheapo Aldi invertor to charge our Bosch powered bikes, but if you get a more expensive pure sine wave invertor you can charge things like tooth brushes which are inductive charge.
Also depending on model of bike you might be able to get a 'car' charger, which should be more efficient.
Also depending on model of bike you might be able to get a 'car' charger, which should be more efficient.
trevskoda
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Most are 36/48 volt so car charger no use, must be the correct unit.
colinm
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When I said 'car charger' that refers to a bike charger for use in a car.
colinm
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The car chargers I'm talking about are plugged direct into 12v and step up the voltage, no invertors involved and subsequently more effcient, at the time of my set up there where none available for our Bosch batteries, they where for a lot of other batteries, but IIRC someone on here pointed out they are about now for Bosch.
trevskoda
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Yes things change from week to week, just always have to keep an eye out, the cigy ones will be a very slow charge as the plug could not pull a big amperage.
colinm
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Most mains chargers are around 70w to 90w (e.g. 36v@2A), ciggy socket ones are pretty much the same.
wildebus
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What kind of Bosch batteries have you got? Probably different to mine (I have the 'Power for All" 12V type of batteries - https://amzn.to/2VoZT7Z ) and mosy of the kit came with a regular 240V AC charger - 13A plug and a large base to plug the battery into.
But one of the tools came with a smaller charging base and a 240V AC - 12V DC transformer style plug. I chopped the lead of that one and fitted a 12V Accessory Plug onto it so I can just plug into a standard 12V socket to charge the batteries with that one
(fitted a little plug and socket on the cable so I can connect the 12V plug or the original 240V Transformer for maximum flexibility).
Ref E-Bike Battery Chargers, I would be surprised if there were DC-DC chargers for those with the high DC voltage they would need. I can't imagine it would be either significantly (or at all) more power-efficient or be cost-effective to get one of those compared to a smallish inverter which could be used for so many other things beside.
colinm
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I'm sure it was on this forum that someone posted a link to a UK website selling car to ebike chargers, might have been OAL. A quick google brings up several. My Bosch mains charger is totally different to your chargers, and it's only approx 85% efficient, add in an invertor and what does that drop too?
My experience of 12v to 20v chargers is that they are considerably more efficient than mains to 20v chargers, this might not apply to 36v chargers.
My experience of 12v to 20v chargers is that they are considerably more efficient than mains to 20v chargers, this might not apply to 36v chargers.
wildebus
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"efficient". What does "efficient" actually mean?
when I look at something, I consider not just power-efficiency, but cost-efficiency.
I have an Inverter (as do many people); I have the 240V eBike Battery Chargers (as all people with eBikes will);
How cost-efficient it is to buy a dedicated DC-DC charger for a specific product? How much more energy-efficient does that need to be over the inverter+mains charger to make it worthwhile to buy? Bearing in mind that you can plug in the AC charger when driving, and plug in if on EHU, and maybe use what would otherwise be excess solar maybe.
Looking at just power efficiency alone is not seeing the whole picture.
colinm
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As per my first post, I too have an invertor whose primary use is charging E-bike batteries, to ensure this worked for us I replaced the original 90Ah of leisure battery with 150Ah of leisure batteries, I might have been tempted to stick with the 90Ah if I had a more power efficient charger, will never know now if that would have worked.
5andy
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I have read this thread with interest, but with little understanding. I would be grateful if you guys could give it one more go to explain this.
We travel with 2 eBikes, which I would like to be able to occasionally charge ‘on the go’, using an inverter. I appreciate it may take some time to fully charge them, but some additional charge would be welcome.
According to the manual, max current charge of the charger is 3 amps. The operating voltage is 54. I have 2 *95 amp leisure batteries.
So the main question is what size of inverter would I require,
a) if we want to charge both together.
But if this is not possible
b) charging just one bike.
Finally, would it be possible to use the cigarette lighter plug, which I would prefer or would I have to attach the inverter directly onto the vehicle or leisure batteries.
Thanks for reading this far into the post.
We travel with 2 eBikes, which I would like to be able to occasionally charge ‘on the go’, using an inverter. I appreciate it may take some time to fully charge them, but some additional charge would be welcome.
According to the manual, max current charge of the charger is 3 amps. The operating voltage is 54. I have 2 *95 amp leisure batteries.
So the main question is what size of inverter would I require,
a) if we want to charge both together.
But if this is not possible
b) charging just one bike.
Finally, would it be possible to use the cigarette lighter plug, which I would prefer or would I have to attach the inverter directly onto the vehicle or leisure batteries.
Thanks for reading this far into the post.
