LiFePo4 legit offer?

[Ampster]

Here you go:

https://www.ebay.com/itm/TYCO-Kilovac-EV200AAANA-Relay-Contactor-Fully-TESTED-USA-model-Low-Use/124426737639?epid=1026357995&hash=item1cf86957e7:g:N4EAAOSwVgdfpKIt

[Ampster]

Can you list the model number and vendor?
For a long time I've been seeking, and have still not found, a BISTABLE, LATCHING relay that can handle high amps and at least 60 volts DC (to be used in a nominal 48 volt system). An item like this would completely solve the quiescent power issue. Thx.

The ones I use are not latching. They respond to loss of power. The manufacturer is Tyco Electronics. Kilovac Czonka Relay P/N EV200AAANA. The coil operates at 12-24vdc. I bought mine slightly used from a local EV conversion shop. I will post a link to some on Ebay. Amazon seems to be overpriced on this item.

[openplanet]

Can you list the model number and vendor?
For a long time I've been seeking, and have still not found, a BISTABLE, LATCHING relay that can handle high amps and at least 60 volts DC (to be used in a nominal 48 volt system). An item like this would completely solve the quiescent power issue. Thx.

[Ampster]

I use a more expensive Tyco contactor that is rated for high Amps and voltage. The main advantage is that is has an economiser circuit the reduces the current necessary to hold it closed to just a few Watts. Since it is on 24/7 a typical relay or contactor coil Wattage would add up over time.

[stekicar]

I looked at the data sheet, and I'm sorry to say that you are mistaken about the maximum voltages. These relays are for VEHICLES, with either 12 or 24 volt electrical systems. The 12 volt model can operate on 9-16 volts, while the 24 volt model can operate on 18--30 volts. High amperage DC currents are extremely hard to break due to arcing, which is why it's almost impossible to find latching relays that can handle high DC currents at voltages higher than the 24 range.

You are correct. I talked to Littelfuse engineer before I purchased contactor and he confirmed that they did not test it for 48V application but he was not against it either. When time permits I will test it and report what I have find out.

[openplanet]

I appologize for late reply but I do not recevice any notification although I am subscribed to this post ...
I hope you found out answer already. But in case, God forbid, you did not:
Relay voltage is not for relay itself but for coil that opens/closes relay. I use 300 amp model "Cole HerseeTerra 880086" and it can withstand 300amp no matter voltage. I hope this answer your question.
Oh, and it is LittELfuse, not littLEfuse ...
This was my order:
Waytek order.png

I looked at the data sheet, and I'm sorry to say that you are mistaken about the maximum voltages. These relays are for VEHICLES, with either 12 or 24 volt electrical systems. The 12 volt model can operate on 9-16 volts, while the 24 volt model can operate on 18--30 volts. High amperage DC currents are extremely hard to break due to arcing, which is why it's almost impossible to find latching relays that can handle high DC currents at voltages higher than the 24 range.

[stekicar]

Here is the breakdown for 1st year (2020) of 720Ah LiFePo4 battery use:
Grid power used per month in kWh: 881, 636, 313, 252, 64, 14, 0, 0, 51, 157, 543, 1157
Total: 4068kWh or $770.39
I have an EV that used 2435kWh for approx 16k miles.
Solar power produced 9417kWh. Unfortunately, hard drive went bad and all my solar data was lost so I cannot show solar production per month.
Calculated PV capacity for my location (SE Michigan) and panel setup is 11513kWh (from https://pvwatts.nrel.gov/). This tells me that my solar setup used 81.8% of its capacity. During June, July and August solar panels produce more than I need and Decembar and January are the worst months and I barely use solar and batteries.
I just installed DIY BMS from Stuart Pittaway to monitor each cell voltage and temperature. Verrrry nicely made system so kudos to Stuart.

[stekicar]

Stekiar--Your high current bistable relays look to be Littlefuse HD series:

https://www.littelfuse.com/products/dc-solenoids-and-relays/bi-stable-latching-relays/hd-series.aspx

From what I can see though, 24 volts D.C. appears to be the highest they offer. How are you using these with your (nominal) 48 volt system? Thank you.

I appologize for late reply but I do not recevice any notification although I am subscribed to this post ...
I hope you found out answer already. But in case, God forbid, you did not:
Relay voltage is not for relay itself but for coil that opens/closes relay. I use 300 amp model "Cole HerseeTerra 880086" and it can withstand 300amp no matter voltage. I hope this answer your question.
Oh, and it is LittELfuse, not littLEfuse ...
This was my order:
Waytek order.png

[PNW_Steve]

I have 16 x 280A/H on the way. It's like waiting for Santa....... Are they here yet??

[Ampster]

When shipped DDP the seller handles shipping and duty and the package comes to your front door.

I agree, DDP, is the way to eliminate any risk of import or duty fees. I used credit cards so I would have that extra protection. My first two orders were six months ago. I just received another 8 cells and they have tested well. They took about 50 days from the time they were shipped until they cleared customs. Fedex delivered them in two business days after that. Over the past six months I have purchased a total of 44 cells from three different supplier with good results.

[PNW_Steve]

Alibaba - unless you know the import & duty fees system well, it's a gamble. Overseas shipments of expensive electronics, unless either store promises how to walk you thru customs.

Ask the seller to ship "DDP" not "DAP".

When shipped DDP the seller handles shipping and duty and the package comes to your front door.

[mstasko]

@hammick No problem! So with Alibaba they have a built-in text feature that I believe most vendors leverage when communicating with customers. In may case the whole deal from negotiating price, what addons to include (buss bars), customs and shipping was done through this feature. I liked the idea of having a 'written' transaction of what was agreed upon before receiving the invoice. So you would want to outline those up front when requesting a quote.

I learned a lot in terms of purchasing from Alibaba and knowledge on "how to" from this site and others (secondlifestorage.com & diysolarforum.com) through folks that already went through this experience.

As for what I am doing with the cells... powering my house. Always had an interest in solar and finally pulled the trigger a couple years ago and started building my system. In short, I learned a ton about our family usage (5 of us) and the original intent was to just offset our loads but once I went through a whole year and compared the performance of the system the gap between supporting 60-80% of our needs to more like 95-100% was small. The biggest gap was in our battery storage, I was losing power most days since our battery bank was topped out and the power had no place to go. Note - net metering is out of the question in my area due to a few reasons, crappy credits, monthly 'convenience fee' being imposed and the threat of future increases with the fee. As a result we self consume everything we produce, no grid tie. The 1120ah bank provides a buffer for those multiple cloudy days.

[hammick]

T

@hammick Hi - in short I purchased 66 280ah EVE cells for $6500, $98 per cell. The price included shipping, buss bars and fasteners. This breaks down to a cell price of $80 a piece and $18 to ship via sea to US. I ordered during the height of the coved lockdowns so everything was delayed and it took almost 60 days to get here. I ordered two extra cells as insurance but ended up needing 7 more since they were damaged in shipping. Ironically the damage was done here in the states by FedX, they manhandled my ordered. Receiving the replacements was straightforward and the vendor shipped them by air for me, although I had to kick in some money to offset the extra shipping charge. Vendor was Deligreen and I would order from them again. If you are in no rush and can wait the extra time then it’s a no brainer from my view to go this route. Btw - the cells I received met my expectations.

Good luck

Looks like the cells are the same unit cost: https://deligreen.en.alibaba.com/pro...ery_280AH.html

Thanks for the great info! I assume I have to call them to confirm the details? Their site is silent on shipping, buss bars and connectors.

BTW what are you guys doing with all these cells. I can't imagine needing 1,120ah of LifeP04 power.

[openplanet]

Stekiar--Your high current bistable relays look to be Littlefuse HD series:

https://www.littelfuse.com/products/dc-solenoids-and-relays/bi-stable-latching-relays/hd-series.aspx

From what I can see though, 24 volts D.C. appears to be the highest they offer. How are you using these with your (nominal) 48 volt system? Thank you.

[mstasko]

@hammick Hi - in short I purchased 66 280ah EVE cells for $6500, $98 per cell. The price included shipping, buss bars and fasteners. This breaks down to a cell price of $80 a piece and $18 to ship via sea to US. I ordered during the height of the coved lockdowns so everything was delayed and it took almost 60 days to get here. I ordered two extra cells as insurance but ended up needing 7 more since they were damaged in shipping. Ironically the damage was done here in the states by FedX, they manhandled my ordered. Receiving the replacements was straightforward and the vendor shipped them by air for me, although I had to kick in some money to offset the extra shipping charge. Vendor was Deligreen and I would order from them again. If you are in no rush and can wait the extra time then it’s a no brainer from my view to go this route. Btw - the cells I received met my expectations.

Good luck

Looks like the cells are the same unit cost: https://deligreen.en.alibaba.com/pro...ery_280AH.html