DIY Solutions to Honda Hybrid Battery Problems (Insight, Civic, IMA)

[MD2000]

Even the D cells used in Hybrid cars need to have special internal construction to deal with the 100A assist and 45A charge that they see on a regular basis.
I took some apart to see what was special.
Stock honda 6.5AH cells dissected:
http://99mpg.com/Data/resources/down...nstruction.jpg

MaxIMA 8AH cell construction (Bumblebee Batteries)
http://99mpg.com/Data/resources/down...nstruction.jpg
http://99mpg.com/Data/resources/down...nnerphotos.jpg

they need a very low internal resistance with multiple welds in multiple places to comfortably handle the currents without overheating.
The photos are an analysis of the differences between different cell construction.
This was a 10AH cell that is not even metal foil.
http://99mpg.com/Data/resources/down...ngkongcell.jpg
The cell self destructed at only 30A.

Another problem with parallel cells is that a short in one cell will suck heavy currents from the other 2 cells, making the pack a dangerous device.
You never see NIMH cells used in parallel for that reason.
Nice idea, but it is not a good or safe replacement for those very special Hybrid D cells in our battery packs.

[ncdave4life]

Hmmm... 10 kW / 144v = 69 A. Ouch, I feel dumb. I should have done that arithmetic.

That's way heavier current than any of the batteries here:
NiMh Battery Shoot Out. {link deleted}

You'd need a 10C or better current rating. The RC (radio-controlled hobbiest) crowd uses batteries like that, but mostly lithium cells, and the Ni-MH batteries which they sometimes use are mostly sub-C size (rather than D or AA), and they're expensive.

Thank you for educating me!

Well, on to plan B, then. Two Chinese vendors on Alibaba list replacement Honda/Insight 7.2V battery sticks at $47-$65, with a minimum order of just 20 sticks. That would be about $940-1300 for a complete set of fresh batteries:
1. KingKong {link deleted} (cheaper, rated 10C & 10A-hr, 1 year warranty)
2. Yabo {link deleted} (cost more, rated 15C & 8A-hr, 5 year warranty)

Has anyone here ever bought from a Chinese vendor on Alibaba? Used their escrow service? Got any advice for doing that?

Also, some of the listings show particular model years; e.g., "2006" or "2003-2005." {links deleted} Is there really any difference (as long as they're in the 1999-2006 range)?

Also, the "KingKong" listing, above, says, "Single 10000mah D cells are also available, you can assemble the stick with our D cells by yourself." My guess is that'd be a lot of extra trouble for little or no savings. Does anyone disagree?

Note: this system wouldn't let me post links, so if you want to see the deleted links go here:
www[dot]burtonsys[dot]com/ecomodder13610.html#2

[MD2000]

The last link I put in my earlier e-mail was a disassembly of the King Kong cells, and this is typical for the 10AH cells in the market.
http://99mpg.com/Data/resources/down...ngkongcell.jpg

They can put out 10Ah, but only at 2-4C, and will burn up if used in Hybrid cars.
Many cells from china were evaluated before the MaxIMA cells were found.

[ncdave4life]

Those must be different cells. For these batteries, KingKong claims to support a 50A charge rate and 100A discharge rate.

This is copied/pasted from KingKong's Alibaba listing (for the link go to www[dot]burtonsys[dot]com/ecomodder13610.html#2):

FOB Price: US $45 - 47 / Piece

Specifications
7.2V replacement NiMH cells for Honda Civic Hybrid
Capacity:10000mah
50A charge rate&100A continous discharge
warranty:3 year

NiMH Rechargeable Battery pack for Honda Civic and Insight hybrid cars

Apply scope: Honda Cvic and Insight 2003-2005

Voltage: 7.2V.

Capactiy :10000mah( Original 6500mah)

Size: 35mm*384mm

Continue Discharge Rate: 100A

Support 50A charge rate

Warranty: 1year

Life span: above 4 years

6 Cell per stack with both ends stainless square and hexagonal standard electric car battery nuts

Our NIMH replacement sticks have passed Vehicle test, we increased the capacity from 6500mah to 10000mah to improve the performance.

Single 10000mah D cells are also available, you can assemble the stick with our D cells by yourself.

I do see that they weren't very careful with their listing. Note that it claims a 3 year warranty near the top, but a 1 year warranty further down. (My guess is that warranty claims w/ Chinese vendors might be challenging, anyhow.)

The Yabo listing is similar, but with higher price, lower capacity and higher discharge rate. They give specifications both for individual cells and 6-cell sticks:

FOB Price: US $55 - 65 / Piece

Specifications
1.Honda Hybrid car battery for sale
2.For Honda Civic/Insight/Prius
3.7.2v/6500mAh
4.HEV level D size cells

NiMH Hybrid Car Battery Pack 7.2V for Honda Civic/Insight

Voltage: 7.2V

Capactiy: 6500mAh/8000mAh

Continue Discharge Rate: 150 ampere

6 Cell per stack with both ends stainless square and hexagonal standard electric car battery

Nuts and inter-connecting cups, rubber heat sealing sleeves and all necessary accessories.

Just plug and replace works that everyone can do it.

For product images, detail technical spec or any other question, feel free to contact.

Item / Specification
Dimensions / Outer Diameter (mm) / 32.2±0.07
/ Over Height (mm) / 60.5±0.2
Approximate Weight(g) / 165
Nominal Capacity(mAh) / ≥6500(IEC)
Nominal Voltage(V) / 1.2
Internal Resistance (mΩ) / ≤1.6
1.2V Discharge Capacity1.2V Cut / ≥70%
Specific Energy (Wh/kg) / ≥45
Peak Power (W) / ≥130(DOD50%)
Specific Power(W/kg) / ≥850(DOD50%)
(30C Discharge,70%SOC,0.8V Cut-off) / ≥10S
Peak Charging (15C Charge, 50%SOC, 1.66V Cut-off) / ≥10S
Max Discharge (15C Discharge, 70%SOC,0.8V Cut-off) / ≥60S
High Temperature Performance(50°C Charge/Discharge Capacity Rate) / ≥70%
Low Temperature Performance(-20°C Discharge Capacity Rate) / ≥80%
Charge Retention(30 Day) / ≥75%
Working Temperature / -20°C to +55°C
Storage Temperature / -40 to +65°C
Cycle Life(C/3 Charge,1C Discharge) / ≥800cycles

2,D Type NI-MH Battery Package(7.2V HEV Battery Bar)
Item / Specification
Dimensions / Outer Diameter (mm) / 34.0
/ Over Length (mm) / 396
Approximate Weight(g) / 1100
Nominal Capacity(mAh) / 6500(IEC)
Nominal Voltage(V) / 7.2
Internal Resistance (mΩ) / ≤9.6
7.2VDischarge Capacity7.2V Cut / ≥70%
Specific Energy (Wh/kg) / ≥45
Peak Power (W) / ≥130(DOD50%)
Specific Power(W/kg) / ≥850(DOD50%)
Peak Discharge(30C Discharge, 70%SOC, 4.8V Cut-off) / ≥10S
Peak Charge(15C Charge, 50%SOC, 9.96V Cut-off) / ≥10S
Max Continuous Discharge(15C Discharge, 70%SOC, 4.8V Cut-off) / ≥60S
High Temperature Performance(50°C Charge/Discharge Capacity Rate) / ≥70%
Low Temperature Performance(-20°C Discharge Rate) / ≥80%
Charge Retention(30 Days) / ≥75%
Working Temperature / -20°C to +55°C
Storage Temperature / -40 to +65°C
Cycle Life(C/3 Charge,1C Discharge) / ≥800cycles

[ncdave4life]

Digression...

Originally Posted by MD2000

...Another problem with parallel cells is that a short in one cell will suck heavy currents from the other 2 cells, making the pack a dangerous device.
You never see NIMH cells used in parallel for that reason...

Actually, multiple-AA - to - D cell "converters" (plastic containers) are widely sold. Most take two AA cells, but some take three. The going price in eBay is $0.99, including shipping. Search eBay for:

2 AA to D

Parallel-connected 3xAA-to-D converters are less common, but do exist.

There are even some 4xAA-to-D converters out there, but the result is a slightly-oversized D cell:
diameter of 1 AA battery = 14.5 mm
diameter of 4 AAs = (1 + sqrt(2)) x (diameter of 1 AA) = 2.4142 x 14.5 mm = 35.006 mm
which is 0.806 mm oversize
compared to the diameter of a standard D cell, which is 34.2 mm

My guess is that if a short developed in one AA cell, it would do so gradually enough that it wouldn't be dangerous, because the stored charge in the other cells would not discharge through the short all at once. (Be careful when loading the batteries into the converter, though, that you don't put in batteries with different initial charge levels!)

Of course, unfortunately, without 10C or better AA cells, none of these could be used in HEV battery packs.

[ncdave4life]

Has anyone here bought batteries through Alibaba? Used their escrow service?

The Yabo batteries are also available via "AliExpress" (part of Alibaba) for $75 each incl. shipping at qty 20 ($1500 incl. shipping for a full set); google for:

honda battery site:aliexpress.com

I don't see the KingKong batteries on AliExpress.

As near as I can tell, AliExpress makes the escrow / "buyer protection" feature non-optional, and is a bit more expensive. Has anyone here used it?

[MD2000]

They are the same cells
Their agent sent them to me for testing after he tried to sell one of my customers a pack worth. The discussions are here
7.2V 6500mah/10000mah replacement battery stick for Honda Civic and Insight 2003-2005 - Insight Central: Honda Insight Forum

The sticks were not even properly welded together, and he could not supply a full stick.

Bottom line
You cannot always believe specifications from Chinese companies.
Good luck

[ncdave4life]

Wow. I sure am getting an education.

I sent a message to KingKong via Alibaba, with a link to this discussion, asking if the Insight/Civic batteries they're advertising are the same as the ones that failed so miserably a few months ago. Maybe someone from that company will comment here.

What do you think of the Yabo batteries?

[ncdave4life]

Originally Posted by ncdave4life

...asking if the Insight/Civic batteries they're advertising are the same as the ones that failed so miserably a few months ago...

Oops, make that weeks ago, not months. I see that on 1/4/2013 a rep for KingKong admitted that their batteries were inadequate for HEV use, and on 1/6/2013 he pledged that they would not sell their sticks until they get the problems fixed.

Obviously they cannot have done that in just 6 weeks, yet KingKong is still advertising the sticks on Alibaba, and even offering to ship up to 100,000 pieces per month. So much for KingKong's pledge.

I hope the Yabo's are better. There's some indication that they might be.

[MD2000]

Need to test the sticks to confirm their suitability, as the KingKong experience has thought us.

Why bother when Bumblebee batteries will sell you a full pack of the 8AH fully tested sticks with proper welding between cells, and hundreds of people using them in civics and Insights.

I believe his pricing is not much more than what the chinese are trying to charge, and he is in the US, in case there is any issues.