New battery (engine bay) Halfords??

Shaw RX · January 1, 2018

Happy new year to all!!!

I need a new Battery for the engine bay - mine has had it. I have a trade card at Halfords so gonna head there today.

Via their website, they do not list the Battery for my 2008 RX400H. Has anyone fitted a Halfords Battery and if so which number?

lurch · January 1, 2018

Some advice, they are the exact same Battery as fitted to a MR2 roadster only about £20 cheaper for the MR2. I have both cars and found this out after I paid more for the Lexus.

Shaw RX · January 1, 2018

8 minutes ago, lurch said:

Some advice, they are the exact same battery as fitted to a MR2 roadster only about £20 cheaper for the MR2. I have both cars and found this out after I paid more for the Lexus.

Makes sense! Thank you. It’s a very small 12v Battery.

So, Halfords don’t list one and won’t specify one. Their policy is they don’t touch batteries on hybrid vehicles.

I dusted off the user manual from the glove box and it says something along the lines of:

Only use a hydrogen Battery specified for your hybrid vehicle. If you fit a standard Battery, you may cause a build up of hydrogen in your vehicle.

Is this nonsense? Surely all 12v batteries are the same??? Apart from size and power etc. I’m finding it hard to accept that a hybrid car needs any special kind of 12v Battery???

January 1, 2018

Hydrogen gas is / may be produced when the 12v lead acid Battery is being charged. Overcharging can result in a dangerous amount.

What page does it state "Only use a hydrogen battery" ? Seems like a misunderstanding.

Britprius · January 1, 2018

All lead acid batteries use the same basic construction, and chemistry. There are three basic versions however.

(1) The flooded lead acid Battery "or normal car battery" uses lead paste based plates immersed in dilute sulphuric acid. These generally, but not always can be topped up with distilled water as this is gassed off in the form of hydrogen, and oxygen while the Battery is being charged.

(2) The AGM (absorbed glass mat) Battery. Uses thinner plates than the flooded Battery, and the acid is held in 95% saturated glass fiber mats between the plates. There being no free acid to spill if the case is broken. The cells are sealed with pressure releaf valves. When being charged some pressure is built up in the cells by the same gasses as in the flooded Battery, but these gasses are turned back into water by a catalyst in the top of the cell, and returned to the plates. The maximum charge rate is usually lower than flooded batteries, but the life span is usually greater even with higher depths of discharge. These batteries are often used in hybrids "often in the cabin area hence the vent tube just in case the Battery is over charged." where they are not used for engine starting, and the charge rates can be better controlled there being no alternator. They are also widely used in medical equipment, mobility scooters, wheel chairs, reclining chairs, and stair lifts where the release of hydrogen gas "explosive", and spilling of acid could be dangerous.

(3)The gel battery has similar build to the AGM Battery, but uses the acid in a gel form. This restricts the charge rate even more keeping it below the level of forming gasses. If gasses are produced by being charged to fast they cannot rise through the gel, and reduce the area of plate in contact with it permanently. This reduces the capacity of the cell. This type battery used correctly has the longest life span

The AGM and gel versions have slightly higher charging and output voltages " 13.8 to 14.2 volts compared with flooded batteries 13.6 to 14 volts.

John.

ColinBarber · January 1, 2018

That warning is normally only given for vehicles that have the Battery inside the passenger compartment (e.g. the boot on the Prius). The Battery needs a special vent hole that a hose connects to, allowing gases to be vented outside. If the vehicle is in the engine bay then there isn't an issue.

Bosch do (or at least did) a Battery that fits which has a slightly higher capacity than the OEM one. I believe it is size 158.

lurch · January 1, 2018

It's just a standard run of the mill Battery nothing special hence its the same on the Toyota MR2 ! I ordered mine from my nearest Lexus dealer in Norwich which was same franchise as my local Toyota dealer so asked them to send it down to the local Toyota garage for me, I paid over the phone and when I went to pick it up the guy in the parts department said if you had ordered one for a mr2 it would have been cheaper! When I got home looked at the MR2 and is exact ! I since have had to have one on the MR2 and same part number.

panasonic T28800-YZZJU. £62.57p 24/05/2017

Shaw RX · January 1, 2018

5 hours ago, lurch said:

It's just a standard run of the mill battery nothing special hence its the same on the Toyota MR2 ! I ordered mine from my nearest Lexus dealer in Norwich which was same franchise as my local Toyota dealer so asked them to send it down to the local Toyota garage for me, I paid over the phone and when I went to pick it up the guy in the parts department said if you had ordered one for a mr2 it would have been cheaper! When I got home looked at the MR2 and is exact ! I since have had to have one on the MR2 and same part number.

panasonic T28800-YZZJU. £62.57p 24/05/2017

Looks like the same one that’s in my engine bay!!!

Thank you for confirming the part number. I will give Toyota a call and see how much they quote me before I try and match it to a Halfords or Bosch one.

gdh300 · January 1, 2018

I was quite surprised how competitive Toyota were for a replacement on my IS. They did have to order it in (came in about five days) but the £89.42 was I though a good price compared to those I found on-line. For comparison, my old Battery and new one had/has these labels:

Shaw RX · January 2, 2018

20 hours ago, Comedian said:

Hydrogen gas is / may be produced when the 12v lead acid battery is being charged. Overcharging can result in a dangerous amount.

What page does it state "Only use a hydrogen battery" ? Seems like a misunderstanding.

Good point!!! I don’t believe it does say that. Are hydrogen 12v batteries even a thing??!!

Shaw RX · January 2, 2018

19 hours ago, ColinBarber said:

That warning is normally only given for vehicles that have the battery inside the passenger compartment (e.g. the boot on the Prius). The battery needs a special vent hole that a hose connects to, allowing gases to be vented outside. If the vehicle is in the engine bay then there isn't an issue.

Bosch do (or at least did) a battery that fits which has a slightly higher capacity than the OEM one. I believe it is size 158.

This makes total sense. Thank you. I feel more comfortable now that I can just use an off the shelf Battery. I’ll have a search for that Bosch one and see how much it is. Thank you.

Shaw RX · January 2, 2018

10 hours ago, gdh300 said:

I was quite surprised how competitive Toyota were for a replacement on my IS. They did have to order it in (came in about five days) but the £89.42 was I though a good price compared to those I found on-line. For comparison, my old battery and new one had/has these labels:

Looks like they put a more powerful one in for you. I guess as long as it fits in the space and has the same power as before, or more, then that’s fine. Thank you.

billgatesisaconman · January 7, 2018

On 02/01/2018 at 10:11 AM, Shaw RX said:

Looks like they put a more powerful one in for you. I guess as long as it fits in the space and has the same power as before, or more, then that’s fine. Thank you.

replacement on my IS < < ...... I take it this isn't the same Battery as the one on the RX ? .....

billgatesisaconman · January 7, 2018

On 01/01/2018 at 10:50 AM, Shaw RX said:

Happy new year to all!!!

I need a new battery for the engine bay - mine has had it. I have a trade card at halfords so gonna head there today.

Via their website, they do not list the battery for my 2008 RX400H. Has anyone fitted a halfords Battery and if so which number?

Hi Steven, can I ask which Battery did you end up fitting .... I think I may also need one.

billgatesisaconman · January 7, 2018

On 01/01/2018 at 12:51 PM, lurch said:

Some advice, they are the exact same battery as fitted to a MR2 roadster only about £20 cheaper for the MR2. I have both cars and found this out after I paid more for the Lexus.

Hi Phil, can you confirm which model/year Mr2 is the same please, and do you happen to know if the Bosch Battery ( Part Number: S4021) is the same size as the one for the Mr2/Rx 400 m8 ... I have a quote for £55 for this Battery from Costco ... they don't list one for the Rx 400 but this one is listed for the Mr2 ... cheers

lurch · January 7, 2018

My MR2 is a 2003 mate, 230mm length X 120 mm wide X 190mm height approx mine I believe to be a Panasonic supplied by Toyota if this helps. You need to just make sure the terminals are located the same as original if you are getting a different make etc mate. + & - in same place.

billgatesisaconman · January 7, 2018

Cheers Phil, I'll get on it tomorrow morning .... ;-)

Ozymandias · January 8, 2018

I replaced mine with a Duracell DA45 from Eurocarparts for about £60 (rx400h 2007). The 5 year warranty was the deciding factor for me.

welland · January 22, 2018

On 01/01/2018 at 12:51 PM, lurch said:

Some advice, they are the exact same battery as fitted to a MR2 roadster only about £20 cheaper for the MR2. I have both cars and found this out after I paid more for the Lexus.

I was staggered to see how small the Battery is under the bonnet of my 2006 RX400H. Is it used to start the engine? That would be very surprising for such a large engine with stop-start technology.

lurch · January 23, 2018

i believe the small Battery only supplies power to the electronics, this then enables the hybrid system to start the car, i dont think the Battery starts the starter motor.

sorcerer · January 23, 2018

13 hours ago, welland said:

I was staggered to see how small the battery is under the bonnet of my 2006 RX400H. Is it used to start the engine? That would be very surprising for such a large engine with stop-start technology.

No, the small 12V Battery powers the entry/exit systems and all the computers to get the car to the 'Ready' state, after that everything is powered by the traction Battery.

welland · January 23, 2018

7 hours ago, sorcerer said:

No, the small 12V battery powers the entry/exit systems and all the computers to get the car to the 'Ready' state, after that everything is powered by the traction battery.

A-ha. (No, not the 80s pop band). Thanks for this. Is it charged by an alternator in a conventional way, or is it charged directly from the traction Battery?

sorcerer · January 23, 2018

45 minutes ago, welland said:

A-ha. (No, not the 80s pop band). Thanks for this. Is it charged by an alternator in a conventional way, or is it charged directly from the traction battery?

No, there's no 'fan belt' and no traditional alternator, it's charged directly from the traction Battery.