So I start off my commute with a pretty long downhill portion (~500m?), and after first testing out my build yesterday, The option I was afraid of happened: braking was disabled after ~50m (over voltage protection kicked in).
I knew this was an option but was hoping maybe the charger would leave enough space in the batteries for the energy from the hill.
Right now I think the simplest option is charging to ~4.0v-4.1v per cell (I have a 6s5p pack), and maybe topping off at work if I need it.
Is there a charger I can program to select a voltage? I have a imax b6 (clone and original on loan from a friend), but they seem to only allow you to go down to 4.18v?
Any other chargers you can recommend?
Any other options?
find one that matches your batteries specs and maybe that could work? Alternatively I have the same problem and I usually just go up 1 hill and that shaves off enough voltage to brake the rest of the way since regen is 20% efficiency at mostā¦
So If I find a 24v CCCV power supply thatās adjustable to 24.6 I could use that as a Li-Ion charger? are there no special functions that make a Li-ion charger āsmarterā than a CCCV power supply?
sure Iāve brought undervolted lipos back with cccv chargers, a power supplys a power supply. Iām not sure what you mean by Li-ion charger but those benchtop cccv chargers are as smart as it gets although not very portable
Looking a bit online, couldnāt find definitive proof you could change the end-of-charge voltage (looked at their manuals and some videos online) are you sure you can change that?
For example, on the imax you can only dial it down to 4.18ā¦
Iām charging 6S lipo with a cc cv step up (boost) voltage converter which is powered from a 19v laptop power supply.
Iāve not had any problems. I donāt believe there is any special charging intelligence in the chargers you mention other than the balancing, which can be done by your bms, and some other features (discharging for example)
With cv cc converter set the voltage to the max you want to reach (24v?), plug it into the bms. The voltage will drop to that of your battery pack and the amps will shoot up to your max (ensure your supply can supply enough power [power = volts x amps] and your batteries can be charged at that rate otherwise turn the current down). As the batteries approach the max voltage you dialed into the converter the amps will reduce progressively until 0amps.
I think they should be called āadjustable max voltage, adjustable max amperageā instead of cc cv, but maybe that doesnāt roll off the tongue quite so well!
I got the boost converter from ebay or aliexpress. Give me a shout if you want more details.
(I used a non cc version first time round, it kept pulling too much power from the laptop charger causing it to cut out through protection mode. Donāt make the same mistake!)
Iām doing the same as @MonkeyM I bought a cc/cv charger on eBay and a 60v watt meter to connect inline with it. I can now charge all my packs to any voltage I would like.
One problem that will occur though is the lack of balancing, if you donāt use a bms they will become unbalanced and even with the bms they only balance the cells at 4.18v at the lowest. So Iām not sure what you will do there, maybe just fully charge the board every second or third ride, or fully charge at work to rebalance the cells
Concerning āhobbyā / rc chargers, i can confirm Turnigy reaktor can be set to any voltage u like.
A cheaper version is Charlsoon (o or similar name) which can be found on banggood for 40-50usd (at least a while ago)
Didnt know isdt alllows only down to 4.15, thats a shame but u can always charge in li-ion mode, i think, turnigy chargers usually charge to 4.1v in this case (or i think they did)