92 CC DS gas, convert to lithium electric rebuild thread

[DaveTM]

Originally Posted by NCPW

I have tested this and found that the ZEVA DOES balance while sleep mode is activated.

Good to know!!

[BBBHC]

Thanks for the feedback!
I figured the sleep mode was mostly for less power draw. Good for "short" periods of time where the cart would sit unused but you may want to be able to use the cart at a moments notice. I believe this would be less taxing on the contactor as well, versus complete power up and power down many times? Otherwise if it didn't balance in sleep mode, I don't think it would really serve a purpose.

I am itching to drive this thing! Too many other things keeping me from it. One of which is my dog. It won't be long now before I have to make the decision.

[BBBHC]

Originally Posted by EmileRenry

Thats very cool, i have thought about building one my self but i havent found a cheap motor with enough power for what i want to do.

Thanks Emile.

What is it you want to do?

[Sergio]

Originally Posted by NCPW

I have tested this and found that the ZEVA DOES balance while sleep mode is activated.

Since the monitor screen is not active in sleep mode, how did You determine the balancing was working?

Was there a time limit? some older documentation from Zeva said there was a 1 hour watchdog timer on the balancing circuit.

[NCPW]

Originally Posted by Sergio

Since the monitor screen is not active in sleep mode, how did You determine the balancing was working?

Was there a time limit? some older documentation from Zeva said there was a 1 hour watchdog timer on the balancing circuit.

Straight off the charger most cells will be orange (in their balance phase) and my pack voltage is 58.4V. I disconnect the SB175 to isolate the pack and BMS from any potential power draws and activate my sleep switch to turn the monitor off. I can check back within a few hours by deactivating sleep mode and some of the cells are still orange (still balancing) and my pack voltage is lower. Check once more by the end of the day and all cells are green (4.14v) and pack voltage is 57.8v.

I've seen you mention a couple of different times (which made me take notice in the first place) that the BMS16 will balance up to an hour after charge completion on other threads, but mine will balance hours after a charge until each cell is at the determined balance voltage I've set.

[Sergio]

I think You meant to say 4.13v for the balance voltage (not 3.14v).

Nice to know that it shunts while in sleep (for auto sleep setup), but I would feel more comfortable if there was a time limit to reduce the possibility of a software bug causing issues.

I think You have a fixed output charger right (not CAN adjustable)? otherwise having the balance voltage equal to the average cell charge voltage would be more efficient.

The 1 hour comment was in some older version of the BMS and I think on some post Ian had made in an Australian forum when talking about shunt balancing techniques and may not apply at all to the current versions.

[NCPW]

Originally Posted by Sergio

I think You meant to say 4.13v for the balance voltage (not 3.14v).

Nice to know that it shunts while in sleep (for auto sleep setup), but I would feel more comfortable if there was a time limit to reduce the possibility of a software bug causing issues.

I think You have a fixed output charger right (not CAN adjustable)? otherwise having the balance voltage equal to the average cell charge voltage would be more efficient.

The 1 hour comment was in some older version of the BMS and I think on some post Ian had made in an Australian forum when talking about shunt balancing techniques and may not apply at all to the current versions.

You're right; I mean't 4.14 per cell. (I edited the original post).

Yes, my charger is a fixed output of 58.4v max charge.

[BBBHC]

So for those of us in cold country, we need to be very mindful of cold temperatures with our lithium batteries. I will be installing a separate 12v battery and accessory system on my cart since I will be installing a winch. With that being the case, I want to install a warmer for the battery pack, so I can use the buggy in cold temperatures. Anyone have a solution for this?

I have not done a whole lot of looking around, but was thinking something like this might work: https://www.amazon.com/dp/B077VLB1KK...v_ov_lig_dp_it

Obviously, would need to get a couple of these, or just one with some sort of insulation.

[DaveTM]

I dunno if you need to heat the batteries. Your in the same climate that I am (Pittsburgh Pa) and I've not had any issues running at temps in the low to mid 20's. (Just keep the windshield up or the face freezes even at 5mph!!)

[Volt_Ampere]

The battery needs to be protected from operating or charging when it's temp is below freezing. (32F, 0C) Performance will drop way off at colder temps but you should not damage the battery operating at 20 deg F. Most Electric cars have to operate in very cold and very hot temperatures so they have battery heaters / coolers. (and fancy liquid cooling systems to transfer heat to / from the batteries) Leaf is an exception - at least the older ones.