Onboard charger for an electric motorcycle conversion?
1 - 11 of 11 Posts
Sorry to nitpick
A cell is a single unit at 3.2V in the case of LFP
That is 32 cell/groups in series comprising your battery, bank, or in this case a pack.
A cell is a single unit at 3.2V in the case of LFP
so 32S is 102Vnominal, best to stop discharge at 96V, 99V even better for longevity.
DIY connections to EVSEs are pretty pricey and bulky.
Best to also allow slower charging from stock 10A 110Vac as well as 240Vac outlets used for driers and electric stoves/ovens in the US.
Brusa, Elcon and DeltaQ make good chargers.
A dumb PSU will do, good ones can be stacked in series or parallel, just use an HVC cutoff
for 32S LFP at between 110-112V
no CV/Absorb stage is required, staying away from vendor max spec V will extend cell longevity without significantly reducing range.
How big is your pack in overall Ah?
Charging amps to get faster than say a 90-120min charge will shorten lifespan.
DIY connections to EVSEs are pretty pricey and bulky.
Best to also allow slower charging from stock 10A 110Vac as well as 240Vac outlets used for driers and electric stoves/ovens in the US.
Brusa, Elcon and DeltaQ make good chargers.
A dumb PSU will do, good ones can be stacked in series or parallel, just use an HVC cutoff
for 32S LFP at between 110-112V
no CV/Absorb stage is required, staying away from vendor max spec V will extend cell longevity without significantly reducing range.
How big is your pack in overall Ah?
Charging amps to get faster than say a 90-120min charge will shorten lifespan.
A word of caution. Some PSUs can't tolerate a sudden loss of load, such as when BMS cuts the charger out. May either need an AC path disconnect for those, or avoid them altogether.
What do commercially produced electric motorcycles use, and can any of that be salvaged and adapted?
The cost and bulk of the onboard equipment to work with common EVSE is certainly a concern, but it would make many more public charging locations available; at home it would be unnecessary, but the intended use is obviously public locations.
Due to the combination of low charging rate and the tendency for charging stations to charge by time (rather than by energy), unless you're using "free" (complimentary, provided by retailers or governments) charging stations this can be an expensive (in terms of cost per kWh) way to charge, but a motorcycle uses so little energy that this might not matter. For example, the only paid public charging station in my area charges $2/hour for AC charging at up to 7.2 kW, which at $0.28/kWh is three times the value of electricity here, and $1.42/kWh if only using 1.4 kW (a typical 120 V onboard charger) which is ridiculous... but still only a few dollars to charge the bike, and $4 for a full charge if following the (reasonable, I think) advice to target a 2-hour charge.
Charging through a J1772 connection to an EVSE can be just as slow as plugging directly into an uncontrolled 120 V or 240 V AC outlet. The EVSE only adds safe and convenient management features, not higher charging rate compared to directly plugging into whatever circuit the EVSE is connected to.
The cost and bulk of the onboard equipment to work with common EVSE is certainly a concern, but it would make many more public charging locations available; at home it would be unnecessary, but the intended use is obviously public locations.
Due to the combination of low charging rate and the tendency for charging stations to charge by time (rather than by energy), unless you're using "free" (complimentary, provided by retailers or governments) charging stations this can be an expensive (in terms of cost per kWh) way to charge, but a motorcycle uses so little energy that this might not matter. For example, the only paid public charging station in my area charges $2/hour for AC charging at up to 7.2 kW, which at $0.28/kWh is three times the value of electricity here, and $1.42/kWh if only using 1.4 kW (a typical 120 V onboard charger) which is ridiculous... but still only a few dollars to charge the bike, and $4 for a full charge if following the (reasonable, I think) advice to target a 2-hour charge.
Zero uses Calex for the standard "pan" charger, and then additionally they sell or sold DeltaQs that could be paralleled for up to 4 units. They sold a J to C13 adapter as well for use with those.
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How often do you plan to use the J1772?
The cutoff relay should control the INPUT to the PSU not its output
I don't believe that's how absolute majority of charging circuits are designed.
Alright. Well, for 48v applications (14s) I use these units Delta MCS-1800 MCS-3000 COVER User Manual To The Bf34cb5c-f204-4c09-9e42-be3d63ebacff and they're quite happy to lose the load when BMS cuts them out on output. At the same time my Chargery C10325 in Power Supply mode crapped out and had to be sent to China for repairs 
Couldn't use it as a charger as it wasn't detecting the pack through the BMS.
Couldn't use it as a charger as it wasn't detecting the pack through the BMS.1 - 11 of 11 Posts
