Pack HV DIY Rebuild

Here's the problem. You will not be able to utilize the additional 3.5 ah on the triangle batteries (unless you can somehow spoof it). The HSD will always think you have a 6.5ah pack and adjust charging/discharging accordingly. Additionally, what is the "C" rating for these cells? Is it compatible with the HSD's regen braking system? I would go w/ OEM.

 

Plus, the leads on the 10 Ah triangles are 24AWG. Unless you could replace the leads, that won't work. The "triangle" cells are really 6 D cell batteries. I don't think they are meant to be scaled up into multi-kwh packs....

 

Our OE Prius modules ARE multicell (6 in series). They also can handle 100A charge/discharge currents (130A in 2010+ modules). D cells would be quickly overheated and destroyed if used in a Prius without reprogramming the ECU to limit the current (as was done to protect the Honda Civic Battery Modules).

JeffD

 

A working battery from salvage (later year the better) is going to be better than a rebuild because all the modules will be of the same age and balance. Moving the modules around center to outside will help increase the life further by evening out the temperature drying affect on the center modules.

 

It's a pity the 10amp/hr cells cannot be used (limited current handling) because, if they were, and are used under the Prius charge discharge system they should last a very long time. The cycle use would only be about 25% of there capacity instead of the 40% of the OEM battery.

 

The capacity of the battery cells is 6.5amp/hr at 1.2volts. 6 cells in a module = 7.2volts. 28 modules in the battery 28x7.2=201.6volts still at 6.5amp/hr this is the capacity of the battery.

The battery can be discharged slowly at say 6.5amps and would last till discharged 1hr.

If discharged at 65amps it would last 6mins at 100amps the maximum rate for the battery it would last 3.9mins. The Prius does draw large current (up to 100amps) from the battery and charges the battery (under regen braking) at high amps.

The battery cells are designed for these loads, other cells such as D cells may have a higher capacity (10amp/hr) but the cannot be charged or discharged at high rates (up to 100amps)

 

+1 To what BritPrius said.

No, the modules are all in series, so whatever current the battery pack is drawing then every module and every cell will draw that same current.

 

If you connect cells in series the amp/hr capacity remains the same as one cell. The voltage is the sum of the number of cells X the voltage of one cell.

If you connect cells in parallel the amp/hr capacity is the sum of the amp/hr capacity of all of the cells. The voltage is the voltage of one cell.

 

Britprius and Uart are correct. all 28 modules are in series as are all 168 cells and if a current is drawn in or out of the HV battery, that current flows through each and every module/cell.

JeffD

 

I am going to go with "No freaking way". Maybe if you put ten in parallel (so 280 in total, over $12,000) they could cope with the current the prius uses. Make it do 10C and at best you waste your money and and worst you cause a fire or small explosion. DO NOT DO THIS! The prius cells are very specialised, and very advanced.

 

Why would you spend $1,300 on those triangle shape batteries? How are you going to house them? Look at the wire gauge size coming out of those batteries and tell me how well they will handle 80A peak current flow without melting. Compare the size of those wires to the bus bars used to interconnect the Prius battery modules.

Honda does not have a reputation for sourcing high performance, long-lasting traction batteries. Ask owners of the older-generation Honda Civic Hybrid whose batteries deteriorated and got no help from Honda other than to change the powertrain management software so that the car relies less on the electric motor. In other words, the car became more like a traditional gas-powered vehicle with an electric motor and battery adding weight but not much value.

The original Toyota NHW10 Prius, sold only in Japan in the late 90's, used D-cell NiMH batteries. That was totally a science experiment. Those batteries were highly unreliable, especially with regards to cell interconnections.

 

If you read the information at Remanufactured Hybrid Vehicle Battery Packs (ReInVolt), you will see that they are promising to supply LiOn-based replacement batteries for hybrids and the Honda Civic is their first target in the next few months. They already have a replacement battery design for the 03-05 Civic Hybrid (and the original Insight) with 30% higher capacity than the OE design (probably not LiON).

They promise a LiOn, high performance HV battery designed for the Prius (Gen1 and Gen2) in 2013.

I have no connection with ReInVolt other than being a satisfied customer of their re-manufactured battery in my 2004 Prius.

JeffD

 

Yes, the Honda cells wold be a poor match for the Prius, as they cannot handle enough current. The cells you are looking at ar not even as good as the Honda cells. The Honda cells are not evem good enough to cope with the lower power demand of the Insight, they would fail very quicklly if you installed them in a Prius. I' be interested in someone doing it a an experiment though!