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[Doctorbass]

I know that the 20Ah EIG cells inside are specified with : 0.5C (recommanded)  that bring a full cahrge for about 2h minimum time... but i wonder what is the max allowable C rate the cell can take?

( I mean REAL NUMBERS, not using the 2 charge port limitation of 30A each for 60A max) but connecting directly to the pack with the charge enable signal to not overcahrge cells

in other words, the cells themself can take wich C rate if taking account of the battery enclusure passive  thermal management?

I know offthegrid charge at multikW but this is not the same , he also have multikWh of battery ( now 18kWh i think) so this would bring to 9kW RECOMMANDED..

now what is the MAX c rate they can take !?

Doc

[protomech]

Terry's demonstrated 20+ kW into his 15.8 kWh pack. No clue what that does to longevity - definitely would monitor cell temperature.

[Lipo423]

Doc,

I would agree with Protomech...do not go above 1C...What for?
You will only reduce pack life span (besides saving some time in a few charges...)

[Doctorbass]

Great.. I also got the confirmation from someone that know these Zero battery very WELL    that 1C is ok

so the ZF9 is a 7.9kWh battery  meaning about 8kW charging power.

curiously 8kW is about the power consumed at 100km/h speed meaning that the ratio of charge time and use time is 1:1 bringing the real cruising speed to 50km/h average during long trip

Doc

[protomech]

Might be a bit more than 8 kW .. or at least I would fall short of 1 hour runtime at 100 km/h = 63 mph.

Terry reportedly uses 7.5 kW at 70 mph = 112 km/h.

A 1C charge rate for him then is 16 kW = 76 km/h average.

[Lipo423]

The nominal capacity is 9Kw...but this is what Zero declares based on manufacturer std. features.
If EIG did the homework in the manufacturing process you should have a little more available capacity but remember that using total capacity means reducing charging cycles...

[Doctorbass]

The nominal capacity is 9Kw...but this is what Zero declares based on manufacturer std. features.
If EIG did the homework in the manufacturing process you should have a little more available capacity but remember that using total capacity means reducing charging cycles...

Guys, no prob i'm famillar with battery engineering , i have my test lab since 2006, but thanks for sharing your info anyway.  I know that using 100% SOC will reduce cycle life. Unfortunatly not all cells are like the A123 wich are not very affected by 100% DOD

In fact Zero specify their battery energy in two different way:

-full charged Voltage x Ah = the way to get the rebate from different program of EV sales. ex: the stock 2011 is 3.9kWh nominal but is specifed as 4.3kWh to get the rebate that start with 4.0kWh battery...

- Nominal voltage x Ah = The right way that give the true energy of the battery.

btw the nominal voltage have been defined as the voltage that a battery have 50% SOC in Wh not AH  and  when measured while dishcarged at 1C if i remember correctly.

I recall that half the Ah does not mean half the energy of the battery because the voltage is higher at the begining of teh discharge so the first 50% SOS have more Wh than the last 50% SOC

so when calculating your trip and max range, dont use the Ah, , use the Wh!.. otherwise the last Ah will be at low voltage and to get the same power on the motor you will need to crank a bit more amp to compensate the lower voltage at the end of discharge

Doc

[WindRider]

Hey Doc Bass,

I am so glad that you got a 2012 model now... Please engineer up a small quick charger based on MeanWell Chargers that can power from 120V or 220V RV Park Style powering options.

Looking forward to reading about your adventures with the 2012 battery pack and some new charging options.

[Doctorbass]

I am preparing an order for 3 Meanwell power supply at ProgressiveRC for a total od 6kW rated and 7.5kW max power.

each cost about 450$ shipped and are rated 2000W but does 2500W when raching constant current and constant power mode.

These operate from 100 to 240Vac and have the PFC feature wich increase the eficiency and draw less current on the AC.

there will be 2 RSP-2000-48 of 42A each wired in parallel for a total of 84A availlable and one RSP-2000-24 of 80A conected in serie.

the RSP-2000-48 will be trimed up to 50.7V and the RSP-2000-24 will stay at 24V so the total volt will be 74.7V wich is the max full charged voltage of the Zero S 2012 and the current will be 80A for a total of 5976W rated power

But these model can give 125% rated current continuous no prob so it can go up to 100A for a total of 7470Watts.

The dimension will be  12"L x 5"W x 4.8"H wich is incredibly small for all that power!.. i might be able to hide it under the 2013 S gas tank i plan on installing also on my 2012. But these are not IP66 so not waterproof.. but still known as pretty strong quality power supply.

meanwell make Power supply since 30 years!

I already have some RSP-1000-48 and RSP-1500-48 and SE-750-24 that i really like but the new gen are twice smaller!! 21.7W per cu in !!

Doc

[WindRider]

Doc,

This sounds ideal.  I would suggest mounting them in a Givi case rather than putting them on the bike all of the time.   Most of my riding is commuting so the on board charger is perfect for that.

Adding a MeanWell charger laden Givi case for Electric touring makes a lot of sense as you don't have to pack the chargers around all of the time and the case also solves the environmental problems.   Just need some kind of quick disconnect to the charging circuit of the motorcycle so that the case with the chargers can be removed.   The dimensions that you give will easily fit in a Givi side or top case.

I have used Meanwell power supplies in telecommunication and WiFi products and have found them to be of excellent quality and nearly indestructible.

Really looking forward to seeing how you implement this.

There is a lot of discussion around quick charging standards but having a flexible solution that can work on any kind of power that can be found out in the world has advantages now, rather than when or if a quick charging infrastructure gets built out.   

RV parks are plentiful in my part of the world and they all have pedestals with large amounts of power available and I would imagine that they would allow an EBike to park there for an hour and juice up for a few bucks in most cases.

[Doctorbass]

The last think i would like to solve is the current adjust that is fixed on these power supply. some of us have searched on the PCB near the current sense shunt circuit to locate some resistors that could be modified for a pot but it was unseccesfull from now.
 
The last idea i had was when i bought some
DC-Dc that take up to 72V input and output 5V at 60A max with adjustable current output but the thing I forgot is to take account of the required voltage span it would need to have to cover all the constant current adjustability since voltage also vary when current vary… In fact, a 75V ( full) battery like the 2012 zero are , does have a voltage range from (18x3.0V)= 54V empty  to (18 x 4.15V)=74.7V full wich mean that the constant current regulation of the charger must be capable of dropping the  voltage down to 54V to not bust the constant current limit. It’s a voltage span of 20.7V.. but unfortunately my DC-Dc are only 0 to 5V… and can not be connected in serie to increase the voltage so…

But the Meanwell idea will work well anyway on a Level 2 charging station or a 240V 40A outlet witch is the goal.
 
 
BTW, The RV park idea is very good!