2021 icon i40 with Roy pow lithium battery locks up

[robertmII]

Jeez man that is scary stuff. Thank god you were ok and kids weren't aboard.

Playing devils advocate here just a bit. Do you have a SOC (state of charge) meter on the cart? With my lithium they installed a separate meter because the factory meter doesn't work. So my SOC tells me how much charge I have left. I believe the roypows shut off at two bars left.

Do you know based on SOC that it was fully charged? Or how many bars were left when it locked up?

[ATrain]

Originally Posted by Pat911

A cart that locks the brakes without power should never be converted to lithium. Lithium will cut all power on a fault condition to protect the cells, in this case injuring or possibly even killing the carts riders in the process.

I'm unfamiliar with the Icon. Can the magnetic brake be disabled? Are there mechanical brakes on this cart?

This exactly. Currently, they should not ever be installed on carts with magnetic brakes without a safety mitigation feature.

It does have mechanical disc brakes as well. Magnetic brake can be disabled, but then the cart drives super weird. Rolls around on hills and when you park it, it wouldn't stay put unless you re-engaged the mag brake.

Originally Posted by robertmII

Playing devils advocate here just a bit. Do you have a SOC (state of charge) meter on the cart? With my lithium they installed a separate meter because the factory meter doesn't work. So my SOC tells me how much charge I have left. I believe the roypows shut off at two bars left.

Do you know based on SOC that it was fully charged? Or how many bars were left when it locked up?

In this case, it's a consumer safety issue I'd imagine. Installing a product where it's known that it has a non-trivial risk of causing serious injury/death is an issue. I want lithium for ICONs though so I want to figure out how to make it work safely.

[Franklpaz]

To be completely honest, I have no idea where the SOC was at. I never thought to look. I’ve had it 4 months, played at least 20 rounds on it and have never had the SOC show less than 50% charge after a full days use, so it never crossed my mind to look.

Update: icon says they changed the motor brake on the cart and are going to test drive the battery to see if the battery has issues. Why would they have needed to change the motor brake to test drive it if there was nothing wrong with it?

[robertmII]

I wonder if the battery wasn't fully charged when you left in the morning. Even though it was plugged in, maybe the breaker popped and it didn't charge all the way, who knows. That would align with what the dealer said about the battery being dead when they got it.

This is a bad situation.

[ATrain]

Originally Posted by Franklpaz

To be completely honest, I have no idea where the SOC was at. I never thought to look. I’ve had it 4 months, played at least 20 rounds on it and have never had the SOC show less than 50% charge after a full days use, so it never crossed my mind to look.

Update: icon says they changed the motor brake on the cart and are going to test drive the battery to see if the battery has issues. Why would they have needed to change the motor brake to test drive it if there was nothing wrong with it?

I'd imagine changing the motor brake is a precaution. A sudden lockup could be a bad electromagnet or the force of the lock might have damaged it. People have been known to break them so they might have just decided replace it.

Does the battery gauge on the factory dash work still with lithium or is it useless?

I just don't see any way a dealer could say "make sure the battery doesn't get too low or you could die" and think that's ok.

[Franklpaz]

The SOC showed it was fully charged when I unplugged it that morning. This is why I don’t fully believe what they are saying.

When you get the lithium add-on for the Icon, the normal battery level reader next to the speedometer no longer works, so that add a separate one which the other poster called SOC under the stock one. This is just red bars with no other readings. All red bars were full when I unplugged in the morning.

[dundeebarnbuggy]

Glad you are OK! I would look into why the cart flipped too. Something is not right. I have locked up the rear wheels on everything from 4 wheelers, pickups farm tractors to golf carts, and unless the machine was sliding completely sideways never had one even think of rolling over.

[robertmII]

I don't understand what happened if it was fully charged when you left and you only went 15 miles. Something went wrong and the battery shut off. If it didn't shut off because of low power then maybe there was a battery failure which caused BMS to shutdown?

Please keep us posted once you hear something back. I have a Roypow Icon as well and am concerned.

[ATrain]

A primary function of a BMS is to protect each cell in the pack from over/under voltage conditions and battery out of temperature ranges (too hot/cold).

It could simply be a bad cell in the pack and the BMS shutdown to try and protect it.

I believe the RoyPows use Prismatic LiFeO4 (lithium iron phosphate) battery cells, which can be more prone to failure over the cylindrical cells. Harder to manufacture and if one bit in the pack is bad, the entire pack is bad. If one cylindrical cell is bad, the BMS can just ignore it and still make due with the other cells.

BMS's can be configured to be "extra-safe", where they shutdown if anything seems out of sync too.

The problem isn't exactly that the BMS shut down because that's expected to happen. It's expected that you can safely drive your cart to empty without a dangerous rollover event.

The only fixes are a separate power source to keep the magnetic brake powered, disabling the magnetic brake, adjusting the BMS (if possible) to switch to a lower-power mode instead of a complete shutoff in the event of an issue, or having the BMS actually communicate with the golf cart controller directly (not feasible with so many controllers).

I'm interested to hear what they're going to tell you as well but this is a technical problem that several of us have been aware of and saw coming. I will say I didn't anticipate a rollover event though, especially with a non-lifted cart and a low center of gravity. Conditions must have been perfect for it to happen.

I hate to ask but...any pics?

[Franklpaz]

I don’t have any pics, but in response to the rollover… my cart has been very tippy from day one. I’m not sure if it’s cause of the lower overall weight from the lithium vs lead acid batteries, but if you take a turn even slightly fast you can feel the front wheel lift off the ground slightly. I was actually looking into spacers to widen the wheelbase before this happened. Tipping on turns has been a concern of mine since the first day I got it. Tipping on straightaways never crossed my mind.

I’ll keep updating whenever I hear back from Icon. But I don’t anticipate hearing from them anytime soon.