Hi all. Does anyone have a view on these discharge converters you see on Aliexpress or ebay? They say it will allow you to connect two or three battery packs at the same time, but none of them actually clarify what technology they are using to achieve this. Are they just blocking diode packs, or relay boxes, or sold-state switching? Your thoughts please!
Discharge Converters?
- Thread starter Cisco-man
- Start date
Those cheap ones are just straight connections between the two batteries. Some sellers actually warn you to ensure both batteries are at the same voltage before connecting together.
More expensive “battery blenders“ are available so you can connect two batteries together and the higher voltage battery won‘t try to charge the lower voltage battery.
I don’t think you can use regenerative braking with proper battery blenders.
More expensive “battery blenders“ are available so you can connect two batteries together and the higher voltage battery won‘t try to charge the lower voltage battery.
I don’t think you can use regenerative braking with proper battery blenders.
Inside the three battery ones are three pairs of ideal diodes, a capacitor and a few other minor components. basically three of these. The two battery ones have two of them, and the one battery ones have zero:
Thanks all. Wow, a total rip-off it would seem. You can put inline diodes in your wiring harness under some shrink tube and get the same effect for £3 ish. I’m all for getting off the bike, turning it off, and unplugging the flat battery, plugging in the fresh one, and away. It’s free and safe!
They're not too much of a rip-off. You can get them for about £20 including shipping from Aliexpress. By the time you've bought the diodes, wire, something to mount them on, some insulation and connectors, you won't be far off that. Obviously, it's cheaper to use just connectors and unplug the battery not in use, which is the method I'd use. It's probably safer too.
I have to disagree. Running two batteries in parallel reduces the stress and sag of the batteries and I think is better, compared to switching batteries.
The mosfets in the product above are better (less loss) than schottky diodes which loose about half a volt at full current.
What mosfets. If id did have mosfets, like the Bosch system, your argument about sag goes out the window.
The mosfets are mentioned in video above at about 5 minutes and as shown in photo below.(which I labeled for your convenience). I'm not sure whether that particular device allows parallel working of batteries or just switches.
Last edited:
Here is a top of the range battery blender at a top of the range price.
It looks like it’s only available through Big Game Bikes in the UK and Spark in the US.
biggamebikes.com
It looks like it’s only available through Big Game Bikes in the UK and Spark in the US.
DATEx2 Parallel Battery Adapter - Big Game Bikes
Upgrade your eBike journey with the DATEx2 Parallel Battery Adapter – the 'battery blender' for seamless rides. Connect up to three batteries, handle diverse types, chemistries, and charge states. Say goodbye to inconvenient swaps! Voltage range: 24V to 84V.
biggamebikes.com
If they're mosfets, where's the 12v to switch them? There's no regulator. The guy said at 5:34 that he didn't know anything about those componets.
Its the ideal diode setup, something like as shown below. I think the (insertion) loss is about 50mV.
Last edited:
An ideal diode uses an active component to drive MOSFETs, then the voltage drop is only tens of mV, not hundreds of mV:
I accept your point fully Sturmey. I’m not rubbishing the tech - the posts that follow show sound functionalities. What I’m decrying is that these are on sale on aliexpress and ebay for small bucks up to big bucks, and we’ve got no simple means of knowing what the box is doing - whether they are safe, ineffectual, or otherwise.
The box itself is miles safer than soldering a couple of ideal diodes in a heat shrink junction. I think the tech is safe but there are always shorting risks. It is best to avoid adding more wiring to your bike unless it's unavoidable.
They are very easy items to test. All you need is a multimeter. I use the older homemade schottky diode version. There is one major supplier presently selling a version for 15 euros so I dont see any reason why I would distrust the technology. Ideal blocking diodes now are dirt cheap as they are used in solar panel installations. I dont see any reason why ebike users should be fearful of new technology that meets their needs once its safe and comes from reputable suppliers. Anyhow that's my opinion.
Double Battery Discharge Converter For E-bike 20A/30A/40A Dual Battery Pack Switch Balancer 24-72VDC
Double Battery Discharge Converter For E-bike 20A/30A/40A Dual Battery Pack Switch Balancer 24-72VDC
www.pswpower.com
Last edited:
I second that, there is a possibility of heat shrink getting shrunk into non existence
PS: I meant if using normal diodes
Fully accepted. I was just being flippant to illustrate a point I was trying to make.
Related Articles
-
MTF Enterprises announces acquisition of EMU Electric Bikes- Started by: Pedelecs
-
Wisper 806T folding bike wins Which? ‘Best Buy’- Started by: Pedelecs
-
Sustrans calls for protected cycle lanes- Started by: Pedelecs
-
Amazon launch their first UK e-cargo micromobility hub- Started by: Pedelecs
