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Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 21 2020 11:13am
by john61ct
john61ct wrote:So are there North American forum members that are known to do good work?
From another thread, just for reference

Litespeed, Alex and Cowardly Duck

No idea where located in the world.

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 21 2020 1:06pm
by Stealth_Chopper
Yes, mister flattie :wink: gossip every day and worry,
Acid, poor thing.
flat tire wrote:
May 21 2019 3:52pm
EM3 is probably more professional than Luna. I don't want to worry about whether the person processing my order is on acid and sends me bottom brackets when I order a motor.

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 21 2020 8:57pm
by Bullfrog
john61ct wrote:
Apr 21 2020 11:07am
Use your Android to Skype
That would be too easy...the Android "device" is an old tablet that does not have a camera or a microphone...and that isn't the only issue. EM3ev wants me to install software on my computer that gives them access to it so they can remotely access the BMS. Since the computer is not owned by me personally, installing unapproved software is not an option. Wrote back to EM3ev offering several options to get the battery repaired as well as an option of credit towards a future battery purchase.

We'll see how things progress...prior to this issue, EM3ev has been very helpful, knowledgeable, and did repair one of the batteries I bought from them back when they had a repair point in Seattle.

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 21 2020 10:05pm
by john61ct
That's just silly, ask around and get a decent Android device for free or certainly under $30.

A techie buddy can easily set you up with a PC to borrow, either running in a VM or he can re-set it back to factory in 10min.

I understand if you don't **want** to do these things, just FYI it's totally straightforward for your average IT-competent person

which has nothing to do with age BTW




Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 21 2020 10:29pm
by bww129
I was considering getting a pack from EM3ev but decided on the Luna Wolf V2 (30Q cells) for the solid construction and magnetic mounting system that's included. It is being used with a Crystalyte H3525, Grinfineon C7240 controller, and CA V3. The controller limits it to 40A so I can't vouch for the 50A BMS limit, but the battery has been great over just a few full cycles with my inefficient throttle management.

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 25 2020 9:27pm
by tomjasz
And you flip a coin to see if there will be a warranty coverage. EM3ev 1 year. Luna? If you manage to embarrass them into support.

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 26 2020 5:34am
by Bullfrog
Has anybody bought a battery from Grin Tech?

I know they are not the subject of this thread but they are what I would consider one of the major three suppliers at least for North America :D . I sure do like Justin and he is always super helpful. Maybe we have been missing out by not utilizing Grin???

I am waiting for somebody to produce a 20s battery capable of 50A continuous and with at least 1,000 Ah. Probably go with EM3ev, Luna, or Grin...whoever makes one first :lol: .

Re: EM3ev vs Luna Batteries and Kits

Posted: Apr 28 2020 6:19am
by tomjasz
Bullfrog wrote:
Apr 26 2020 5:34am
Has anybody bought a battery from Grin Tech?

I know they are not the subject of this thread but they are what I would consider one of the major three suppliers at least for North America :D . I sure do like Justin and he is always super helpful. Maybe we have been missing out by not utilizing Grin???

I am waiting for somebody to produce a 20s battery capable of 50A continuous and with at least 1,000 Ah. Probably go with EM3ev, Luna, or Grin...whoever makes one first :lol: .
Yes, first class batteries from Justin.

Re: EM3ev vs Luna Batteries and Kits

Posted: May 27 2020 9:07pm
by thender
I bought a battery from EM3EV. It had an issue with shipping where they would've been in the clear even if I filed a chargeback(which I never threatened to do, I am just saying that they would've been able to keep the money). They expressed me a 2nd one anyway. When the 1st was found I paid for it because of how well they handled me.

I bought something from Luna I needed quickly. They do not have a more expensive or express shipping option. I sent them a shipping label for the item using express shipping, using the same courier they use for their normal shipments so they wouldn't have to schedule a pickup or make a trip outside their normal schedule, and they said they couldn't use it, or offer express shipping even if I wanted to pay for it. I remember stuff like that.

If I am asking you to use fedex, and you have a USPS pickup, or to use UPS when you have a USPS pickup, I get it. Screw scheduling a fedex pickup for a one time order, and screw driving to the store for one order. But if I am asking you to take my label I paid for, and put it on the box, and give it to the courier you give other orders to anyway, AND keep the money I paid you for shipping and pocket it... can you work with me a little?

I only buy from luna when I need something I can't find anywhere else, and even then.

Re: EM3ev vs Luna Batteries and Kits

Posted: May 28 2020 5:16pm
by flat tire
Stealth_Chopper wrote:
Apr 21 2020 1:06pm
Yes, mister flattie :wink: gossip every day and worry,
Acid, poor thing.
Lol, what does that mean? I had a ridiculous ordeal with Luna and the people I spoke to on the phone weren't sober. Recreational drugs are great but probably not for people trying to be professional at work. To clarify, I don't consider acid a recreational drug and I don't actually think they were on acid. Just stoned and stupid. Although Eric has definitely done some acid in his time and I'm not sure the results are what one would want.

Re: EM3ev vs Luna Batteries and Kits

Posted: May 28 2020 6:32pm
by Stealth_Chopper
:lol: You poor professional clarified thing; diagnosing sobriety over the phone because you're a psychic mind reader.
.

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 29 2020 3:40pm
by tomjasz
Bullfrog wrote:
Apr 21 2020 5:50am
PC. Send me a shipping label so I can send the battery to them for repair.

To be continued...
OK continue?

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 29 2020 4:49pm
by Bullfrog
Latest on my 14s5p HG2 cell battery from EM3ev.....

Never could work out the details to reprogram my BMS. EM3ev ended up sending me a new BMS that is supposed to constantly balance the cell groups when charged above about 90%. I installed the new BMS and have charged to battery to 100% over 20 times...I stopped counting after 20. It started out with about 8.5 Ah capacity and is rated at 14.8 Ah...over the course of the 20 charge cycles, the capacity increased very incrementally to 11.8 Ah and has now started to decrease just a little bit...but the highest it ever got was 11.8 Ah. I don't run it down completely every time I use it but I do use my Cycle Analyst occasionally to measure the full capacity from 100% to when the Low Voltage Cut Off turns the battery off.

I sent an email to EM3ev one week ago today asking if there is anything we can do to resolve the situation and have not heard anything yet.

EM3ev no longer has repair capability in North America so if you have a problem, you are on your own and about all EM3ev will do is provide a new BMS or On/Off switch.

My opinion is that I have a week cell group that is causing the problem but no way to remedy the situation.

Above is the bad news. The good news is IMO, EM3ev builds the best battery available right now. Sort of ironic but that is my opinion.

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 30 2020 10:11am
by The Mighty Volt
Just regards EM3EV I have been looking to get

1. Technical advice
2. Buy a new 12t Rear Mac

.........sent them an email yesterday and have not heard back yet. That's not unusual per se, due regard to the WuFlu etc.

However, their not having any Mac motors listed for sale is very unusual indeed. Only motors they have are those BafangMids.

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 30 2020 10:52am
by Bullfrog
EM3ev no longer sells the MAC. You can do a one time order directly from MAC...just tell them you would like to buy one motor as a "sample". You can also buy a controller from MAC...I like the Infineon 12 FET IRFB3077 to run with a MAC and a 52v battery. After your first purchase, there is a minimum order of eight motors :shock: .

Get a Cycle Analyst from Grin Tech or other source (Grin Tech designed it and has it produced).

The MAC is my favorite motor...I have been running a 12T MAC in a 27.5 MD35 Alex rim with a Schwalbe 2.8 Super Moto-X tire and the top speed with a 14s battery is about 26 mph... You may want to go with a smaller diameter rim/tire because it will make your motor run cooler. As wonderful as the MAC is, it does have some limitations you have to operate within or it will overheat. You can set your Cycle Analyst to protect the motor...I would recommend going no higher than 130C roll back and 140C shut down. A little lower would be safer...like 120C roll back and 130C shut down.

If you are going to ride off road at speeds below about 20 mph, the MAC is not the motor for you...go with a BBSHD.

Want to go over about 30 mph (10T required), the MAC is not the motor for you...go with a Direct Drive Hub motor.

Riding between about 20 and 30 mph...the MAC is awesome and will out accelerate ANY motor from 0-20 mph :wink: .

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 30 2020 5:30pm
by john61ct
Are you saying the main battery problem is that you are getting lower "actual in use Ah" capacity

compared to the "theoretical / optimistic" vendor cell ratings?

IME completely normal, not necessarily a indication of anything being grossly faulty.

I take it you did not get a BMS that shows what's going on per cell/group?

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 30 2020 5:58pm
by Bullfrog
I can get the cell group voltages...that is how I know there is a low cell group.

The capacity of a 5p battery with HG2 cells should be 15 Ah per the battery cell manufacturers data. EM3ev rates it at 14.8 Ah and the best I have gotten is 11.8 Ah...and that was after installing the new BMS that constantly balances the cell groups when charging and charging to 100% over 20 times. The balancing is a very slow and gradual process with incremental changes to the weak cell group each time the battery is charged.

The 3 Ah per cell group is based on actual test data from LG...nothing theoretical about it.

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 30 2020 11:17pm
by john61ct
No but they got that at 0.1C or even slower, and using the most extreme voltage possible at bothe ends

Not saying you haven't got a real problem, just that best case scenario the "saner" way you measure might see at least 10-15% less than the spec.

If you have access to the cell/group balance leads maybe forget that BMS for balancing,

maybe do it manually?

or get a balancer that works at any voltage, maybe active shunting rather than just discharging the higher ones, uses a higher rate independent of the Vdelta

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 31 2020 9:23am
by fechter
If you have a way to charge the pack at a current that is less than the balancing shunt current (typically 50mA or so), you could let it go for a long time and it should eventually bring up the low cell groups. If you can access the cell connections at the BMS, it would be faster to manually charge the low group.

Re: EM3ev vs Luna Batteries and Kits

Posted: Jul 31 2020 6:33pm
by Bullfrog
fechter wrote:
Jul 31 2020 9:23am
If you have a way to charge the pack at a current that is less than the balancing shunt current (typically 50mA or so), you could let it go for a long time and it should eventually bring up the low cell groups. If you can access the cell connections at the BMS, it would be faster to manually charge the low group.
Thanks fechter...I'll give the low amperage charging a try.

Since the pack is sealed with RTV...it is a pain to open it, clean it, and reseal it repeatedly to keep it water tight :wink: .

john61ct...Thanks for the ideas.

Re: EM3ev vs Luna Batteries and Kits

Posted: Sep 12 2020 3:02pm
by markz
thender wrote:
May 27 2020 9:07pm
fedex
I ordered some stuff from Luna (California USA) and I figured in the hidden cost of $44cdn FedEx Ground fee for international shipping to Canada from USA. I just wanted it sooner then months later (CycloneTW - China)

A few months ago there was another thread posted from a Canadian ES user asking about Luna and FedEx, I am too lazy to find the post. What happens with Canadians using FedEx ground from USA to CAD is you receive the shipment from Luna, and about 1 month later you get a happy letter in the mail from FedEx asking for additional C$44, its happened to me twice, the first time was a learning experience, the second time I knew the true cost.

The current problem I have is I cant get the Cyclone 4kw mounting plate off the BB on one side. It maybe just that the BB removal tool isnt long enough to get over the axle, thats why the BB tool barely fits in. I will be out of action for another 3 weeks and with covid prolonging over seas shipments who knows how long Cyclone Taiwan will take.

Re: EM3ev vs Luna Batteries and Kits

Posted: Sep 12 2020 3:46pm
by Bullfrog
markz...you know Grin Tech is in Canada. Maybe Justin can help you :D .

I have to give a huge THANK YOU to express to EM3ev and take back anything and everything negative I have ever implied or said about them. Bought a 14s5p battery with HG2 cells back in Nov '19 and it never would fully charge. They sent me a new BMS which was supposed to fix the problem...well the new BMS helped a little but did not completely solve the problem. Now EM3ev is sending me a replacement battery at no cost to me...unfortunately they can't get the HG2 cells right now so they are sending me a 14s6p pack with 25R cells which will have equal capacity to what the 5p HG2 pack should have had when new. Another plus on the 25R cells is they are capable of a higher C rate so I can discharge a higher amperage but I'll still have the same Amp Hours.

I guess Luna, Grin Tech, and EM3ev all have their good points but for batteries, it is tough to compete with EM3ev IMO :wink: .

As far as hub motors and tech support...Grin Tech IS the best and Justin has put out some youtube videos that are absolutely awesome so if anybody needs a hub motor...geared or direct drive, I'd go to Grin Tech.

Luna has their own little niche...like the Cyclone but IMO you get what you pay for with the Cyclone and it is a little less expensive than the BBSHD 8) . Luna does sell complete bikes where the other two don't.

Just my personal experience and opinion :D .

Re: EM3ev vs Luna Batteries and Kits

Posted: Sep 12 2020 4:11pm
by john61ct
And thanks, we need all the decent vendors we can get in this business, glad to hear EM3ev is doing the right thing

Re: EM3ev vs Luna Batteries and Kits

Posted: Sep 29 2020 4:02pm
by Bullfrog
UPS just delivered my 14s6p battery from EM3ev...it is a replacement for a HG2 cell battery that never would fully charge.

The new hard plastic case that surrounds the battery looks very nice and protective and it comes with a triangle bag with Velcro straps to attach everything to your bike.

Anyone needing a battery....I'd highly recommend EM3ev and their 14s6p configuration. They have multiple cell options depending on whether you need high capacity or high amperage.