12v Battery purchase

12v

(David Bennett) #1

Dear All, I’m looking to purchase the 12v battery. Any pointers as to where I might get one?
Thanks V much
David


Not turning on
#2

Renault quote £90 +VAT. I bought one from Tayna.co.uk for £37.98 inc (free del)
It has spade connectors so I had to drill a hole to refit the cables. Another option would be to use piggy back spade connectors.

The original battery (2.5 years old) was flat and measured only 4.65v… It charged back up to 12.9v but I preferred to replace it for peace of mind. I’ve since had it tested and it is declared healthy. I’ll keep it for a back up.


(m1n1s) #3

I brought one off ebay and went with the piggy back spade connectors.

Spade connectors make for a better contact area to the battery connectors, drilling them out reduces the surface area and could result in the contacts becoming warm during high current drain.

The piggy back spade connectors had m6 holes in to bolt the original battery leads.

Original battery was in a terrible state - not seen any service i think , plenty WD needed to remove the terminal screws :slight_smile:

My original Renault battery was date coded as November 2010.


#4

Right, so the new battery went flat in 5 days during which I did two 23 mile trips. I’m fairly sure that the lights, wiper, hazards and heated windscreen are all off and not drawing any current. The Parrot seems to only come on with the key switch and I have a Power Box plugged in but I’ve had that since January and it’s not caused a problem. Something must be drawing current from the 12v battery when parked in the shed (sorry - Twizy accommodation).

There is a click/clunk when I reconnect the battery and I wonder if 12v is used to hold open a switch to the traction battery and then closes when I switch on, in which case something must have changed because I haven’t had this problem before in a year of use.

A wiring diagram would be useful but as the fuse page in the manual is as much use as a chocolate oven glove I don’t hold out much hope that Renault have made that available.

If there isn’t a solution I’ll just use @ALEXAKOS trick of wiring in a socket for a 12v charger. and keep it topped up.


(Fredrik) #5

Hello
Maybe your battery is not getting charged? Will you get it running again if you put you Twizy on charge?
The old cars charged the 12 volt battery when you charged the car, the newer ones charges the 12 Volt battery from the Big battery if I have understood it right…
Fredrik


(osbrook) #6

I don’t think the two are separate. The 12V charges when the Twizy is being charged and directly from the Traction battery (DC-DC) when the ignition is turned on. However this cannot happen if there is no power in the 12V battery to switch over the relays.


#7

Thanks @Sciroccogtx16v and @osbrook, both batteries restored normal operation when recharged but that doesn’t explain why they went flat. I’ve ordered a Ctek Battery Sense to keep an eye on the 12v battery and get an idea of when it’s discharging. I’ll report back.


(Matt West) #8

So where do you get those spade connector extensions from?


(m1n1s) #9

in my garage , lots of old classic minis here but i’m guess these can be brought on the high street


#10

I’d be cautious about using the spade terminals for two reasons: 1) They’re a lot thinner so may not be designed for the current draw and 2) They’re not designed for the high vibration environment in the Twizy.

You could mitigate 2 by bolting as someone has done but personally I wouldn’t cut corners for the sake of 50 quid or so.


(osbrook) #11

Spade connectors will handle more than double the current that is coming/going to the Twizy battery.

Vibration isn’t a problem if fitted correctly - look at a Washing machine plenty of vibration there. Besides there are spade connectors all over cars without issue. Look at headlight bulbs.


(m1n1s) #12

had no problems since fitting them, nothing has over heated or fallen off :slight_smile:


#13

Manufacturers don’t spend money unless they have to. The Twizy 12v battery is bespoke and it will be for reasons unknown to us. Having worked for OEMs I can assure you they would have gone for the generic battery if they could.


(osbrook) #14

I see it the other way round. Renault got a good deal on ‘special’ batteries that they can buy for the usually price and mark up and sell on for a big profit. The battery manufacturer would have not charged extra for the battery as they had a captive market from Renault. It was only the external connections that are different so no issue to them.

Renault and Battery manufacturer win win - Users pain in bum or pay silly money.

Remember the alternatives are slightly high capacity for the same size.


(John Wilson) #15

Anyone tried a 12ah LiFePo4 in this application?


(osbrook) #16

Is that the one with the built in BMS so can directly replace a Lead Acid Battery?


(michael burles) #17

Just got a new battery from Tayna.co.uk for less than 1/2 price of a Renault battery which they do not keep in stock. As advised had to drill out a hole to secure the cables. I went for the heavy duty golf buggy battery which is the same size and the positive post is on the correct side. Thanks very much Silas for the info. Twizy works fine now.


(John Wilson) #18

This one


(osbrook) #19

If you read on the side it says use only the charger provided. This means you would need to disconnect /disable the high current charger in the Twizy as it will damage the LiPh battery.

It is not even as simple as remembering to disconnect it before charging the Twizy and charging the 12v separately as the Twizy re-charges the 12V battery when it feels it needs too. ie. lots of lights and windscreen wipers.

For car sized direct replacements there are some drop in replacements and the electronics handle the battery charging taking what it needs form the alternator etc.

Basically Lead acid and Lithium batteries need to be charged differently.


(John Wilson) #20

The tech specs say Max charging voltage 14.4 V, up to 12A charging current. Typical lead acid chargers only go up 4 amp for this size of battery. LiPO and LiFePO4 are different chemistries, the LIPO ones are more likely to catch fire than the other ones.

Any idea what the Twizy outputs?